Conscientiousness and online education.page

---
description: Technology-driven shift in demand for Conscientiousness, not intelligence
tags: psychology, sociology, meta-analysis, anime
created: 20 Jul 2012
belief: possible
status: in progress
...

[Online education](!Wikipedia) like [Khan Academy](!Wikipedia) has been hailed as a major innovation which will revolutionize higher & lower education, educate students better, and cut costs. They're an interesting idea and worth trying though overall, I take a fairly skeptical attitude towards MOOCs: they seem like a clear example of Amara's Law ("We tend to overestimate the effect of a technology in the short run and underestimate the effect in the long run."), and in general are not doing a good job of exploiting the possibilities of the Web (no MOOC I've seen provides a learning tool even a tenth as good as Bret Victor's [Up and Down the Ladder of Abstraction](http://worrydream.com/LadderOfAbstraction/)).

One of the questions that interests me is the possible long-term effects. In general, changes do not preserve all relative positions or ratios - someone benefits disproportionately, someone benefits only a little. It seems highly unlikely to me that online education will reduce all costs equally, or educate all students better by the same degree.

So what differentials can we expect from online education? Hoary articles from the '90s about the '[digital divide](!Wikipedia)' might make one predict that it will benefit middle and upper-class whites; but on the other hand, proponents love to talk about favored minorities (eg a foreign black female, like a girl in an African village) who can now access online education through cheap cellphones, so one might predict instead that online education will instead help level playing fields. No longer will there be a big gap between receiving essentially no education and receiving a real education, a gap that perpetuates cycles of poverty. As Internet access becomes *more* common than access to quality schools, quality school delivered through the Internet will lead to an equalizing effect (the elites will be no better off than before, and the non-elites now have the chance to obtain a prerequisite to becoming an elite).

# Success factors

It may help to ask what causes success in education and see how online education affects it. To a first approximation, ignoring environment, one earns educational success through:

1. [IQ](!Wikipedia)/_g_

    IQ obviously predicts a huge chunk of educational success (leading to the ironic accusation that IQ tests are only academic questions) since the smarter one is, the easier learning anything is, much less one's schoolwork.
2. [Conscientiousness](About#fn26) (a personality trait in the [Big Five](!Wikipedia "Conscientiousness#Personality models"); of the hard work, grit, effort)

    If one is not smart enough that one can simply inhale lessons and pass tests, one still has the option of *working hard*: doing extra practice problems, asking for help, etc. Success will not come easy, but it will still come. These 2 factors together will correlate somewhere like 0.7 with educational success: someone who is smart and hard-working will go to the top, and someone who is stupid and lazy will not.
3. Miscellaneous

    The rest of the correlation is made up of socioeconomic status, culture (eg. East Asian?) and [random other things](http://people.virginia.edu/~ent3c/papers2/Turkheimer.Nonshared-Environment.pt1.pdf "'Nonshared Environment: A Theoretical, Methodological, and Quantitative Review', Turkheimer & Waldron 2000"): random life events or hard-to-measure environmental factors like an extra-inspiring teacher, etc.

## Conscientiousness

IQ is very well studied, with a thorough literature going back nearly a century; it correlates with [scads of good outcomes](http://www.udel.edu/educ/gottfredson/reprints/1997whygmatters.pdf). But Conscientiousness is far more obscure, so it's worth giving background on why we might mention it in the same breath as IQ.

A [famous & much-cited](http://people.tamu.edu/~mbarrick/Pubs/1998_Mount_Barrick.pdf "'Five Reasons Why The `Big Five` Article Has Been Frequently Cited', Mount & Barrick 1998") 1991 meta-analysis, Mount & Barrick's ["The Big Five Personality Dimensions and Job Performance: A Meta-Analysis"](http://people.tamu.edu/~mbarrick/Pubs/1991_Barrick_Mount.pdf) found that Conscientiousness correlated (~0.2; possibly ~0.31) with various job performance measurements even after controlling for all the obvious thing like IQ & education, as did [a followup survey](/docs/conscientiousness/1996-costa.pdf "'Work and Personality: Use of the NEO-PI-R in Industrial/Organisational Psychology ', Costa 1996") in 1996. Conscientiousness correlates weakly [with](/docs/conscientiousness/2003-lounsbury.pdf "'Intelligence, `Big Five` personality traits, and work drive as predictors of course grade', Lounsbury et al 2002") [IQ](http://www2.psych.ubc.ca/~heine/docs/2008Mccrae-rejoinder.pdf "'What Do Cross-National Comparisons of Personality Traits Tell Us? The Case of Conscientiousness', Heine et al 2008") in the first place (but [maybe not](/docs/conscientiousness/1997-allik.pdf "'Intelligence, Academic Abilities, and Personality', Allik & Realo 1997")); correlates with success in [medical school](http://users.ugent.be/~flievens/increase.pdf "'Personality Scale Validities Increase Throughout Medical School', Lievens et al 2009") or [as a teacher](http://www.sas.upenn.edu/~duckwort/images/Positive%20predictors%20of%20teacher%20effectiveness.2009.pdf "'Positive predictors of teacher effectiveness', Duckworth et al 2009") or in [spelling bees](http://www.sas.upenn.edu/~duckwort/images/Deliberate%20Practice%20Spells%20Success.full.pdf "'Deliberate Practice Spells Success: Why Grittier Competitors Triumph at the National Spelling Bee', Duckworth et al 2010") along with all the correlations with educational success ([Noftle & Robins 2007](/docs/conscientiousness/2007-noftle.pdf "Personality Predictors of Academic Outcomes: Big Five Correlates of GPA and SAT Scores"); [Poropat 2009](/docs/conscientiousness/2009-poropat.pdf "A Meta-Analysis of the Five-Factor Model of Personality and Academic Performance"); [Hsu & Schombert 2010](http://arxiv.org/abs/1004.2731 "Data Mining the University: College GPA Predictions From SAT Scores"); [Chamorro-Premuzic & Furnham 2008](http://ion.uwinnipeg.ca/~clark/teach/2700/Chamorro.pdf "Personality, intelligence and approaches to learning as predictors of academic performance")) and in particular may determine one's success in *online* education ([Elvers et al 2003](http://www.anitacrawley.net/Articles/elversAttitudinalDifference.pdf "Procrastination in Online Courses: Performance and Attitudinal Differences")); correlates [with educational credentials](/docs/conscientiousness/1999-judge.pdf "The Big Five personality traits, general mental ability, and career success across the life span") after mental ability has been controlled; correlates with not having [been in jail](http://inductivist.blogspot.com/2010/11/religiosity-big-5-and-jail-time.html) and predicts later [criminal records](/docs/conscientiousness/1994-krueger.pdf "'Personality Traits Are Linked to Crime Among Men and Women: Evidence From a Birth Cohort', Krueger et al 1994"); correlates [more strongly](http://www.subjectpool.com/ed_teach/y4person/1_intro/refs/Caspi_Roberts2005_AnRevPsych.pdf "'Personality Development: Stability and Change', Caspi et al 2005") ([summary](http://econlog.econlib.org/archives/2009/06/does_personalit.html "Does Personality Matter? Compared to What?")) than IQ with socioeconomic status (SES) and [lifetime income](http://www.iza.org/conference_files/CoNoCoSk2011/gensowski_m6556.pdf "'The Effects of Education, Personality, and IQ on Earnings of High-Ability Men', Gensowski et al 2011"), and almost as strongly as IQ with occupational status (and predicts [employment](http://kops.ub.uni-konstanz.de/bitstream/handle/urn:nbn:de:bsz:352-165477/Pohlmeier.pdf "'Unemployment Duration and Personality', Uysala & Pohlmeier 2011")); like IQ, Conscientiousness correlates with [being thinner](http://www.apa.org/pubs/journals/releases/psp-101-3-579.pdf "'Personality and Obesity Across the Adult Life Span', Sutin et al 2011"), [reduced mental & physical disease](http://midus.wisc.edu/findings/pdfs/360.pdf "'Health Status and the Five-factor Personality Traits in a Nationally Representative Sample', Goodwin & Friedman 2005"), and [longevity](/docs/conscientiousness/2011-hill.pdf "'Conscientiousness and Longevity: An Examination of Possible Mediators', Hill et al 2011") (both as [children](/docs/conscientiousness/1993-friedman.pdf "'Does Childhood Personality Predict Longevity?', Friedman et al 1993") and [adults](/docs/conscientiousness/2008-kern.pdf "'Do Conscientious Individuals Live Longer? A Quantitative Review', Kern & Friedman 2008"); see also [Bogg & Roberts 2004](/docs/conscientiousness/2004-bogg.pdf "Conscientiousness and health-related behaviors: a meta-analysis of the leading behavioral contributors to mortality"), [Hampson & Goldberg 2006](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1363685/ "Forty Years On: Teachers' Assessments of Children's Personality Traits Predict Self-Reported Health Behaviors and Outcomes at Midlife"), [Turiano et al 2013](https://www.ncbi.nlm.nih.gov/pubmed/24364374 "Personality and the Leading Behavioral Contributors of Mortality")); correlates (0.4) with 'overall quality of life' and (0.25) 'happiness' (Steel et al 2008, ["Refining the relationship between personality and subjective well-being"](http://www.subjectpool.com/ed_teach/y4person/3_happiness/Steel2008_5FM_and_happiness_psych_bull.pdf)). [Some studies](http://web.archive.org/web/20080904222633/http://www.psych.umn.edu/courses/spring08/mcguem/psy8935/readings/roberts2007.pdf "'The Power of Personality: The Comparative Validity of Personality Traits, Socioeconomic Status, and Cognitive Ability for Predicting Important Life Outcomes', Roberts et al 2007") show correlations to divorce rates, SES, *and* longevity; or simply on nearly every behavior relevant to longevity (see [Roberts & Bogg 2004](http://web.archive.org/web/20120126082753/http://internal.psychology.illinois.edu/~broberts/Roberts%20&%20Bogg,%202004.pdf "A Longitudinal Study of the Relationships Between Conscientiousness and the Social-Environmental Factors and Substance-Use Behaviors That Influence Health")). [A study](http://www.iza.org/conference_files/CoNoCoSk2011/gensowski_m6556.pdf "'The Effects of Education, Personality, and IQ on Earnings of High-Ability Men', Gensowski et al 2011") of the [gifted Terman kids](!Wikipedia "Genetic Studies of Genius") (similar to [SMPY results](http://www.vanderbilt.edu/peabody/smpy/Ferriman_2010.pdf "'Beyond the Threshold Hypothesis: Even Among the Gifted and Top Math/Science Graduate Students, Cognitive Abilities, Vocational Interests, and Lifestyle Preferences Matter for Career Choice, Performance, and Persistence', Ferriman Robertson et al 2010")), found that for these bright-to-brilliant kids, Conscientiousness affects lifetime earnings (usually $2-3 million) even more than IQ (although only a bit more than [Extraversion](!Wikipedia)); this is not due *solely* to it increasing how much education the participants got. Eyeballing [the graphed correlations](http://2.bp.blogspot.com/-NYuq-8LEK_Q/TZgO5KCPb7I/AAAAAAAABJw/0ifRBv1nX28/s1600/Screen%2Bshot%2B2011-04-02%2Bat%2B11.04.19%2BPM.png) on page 45, it seems that going from the 10th percentile of Conscientiousness to the 90th was worth *~$800,000*. (It's worth noting that there is a ['Grit'](!Wikipedia "Grit (personality trait)") which is [very similar](!Wikipedia "Grit (personality trait)#Grit and Personality Measures") to Conscientiousness with longer-term perspective and less feedback, but which [seems to correlate better](http://www.sas.upenn.edu/~duckwort/images/Grit%20JPSP.pdf "'Grit: Perseverance and Passion for Long-Term Goals', Duckworth et al 2007") with GPA, military academy graduation, and spelling bee performance.) Along with [Openness to Experience](!Wikipedia), Conscientiousness is one of the main correlations with [creative scientists](http://lesswrong.com/lw/9m6/the_personality_of_greatcreative_scientists_open/ "The Personality of (great/creative) Scientists: Open and Conscientious") (stronger than Introversion!).

And there is one key difference between IQ and Conscientiousness: increasing IQ is a tricky and often impossible task, but there is weak evidence that Conscientiousness [can be improved](http://commonsenseatheism.com/wp-content/uploads/2011/02/Eisenberger-Learned-industriousness.pdf "'Learned Industriousness', Eisenberger 1992") by trying harder tasks. (There is an irony here - it's hard tedious work to develop the ability to do hard tedious work, so how does one start?) Interestingly, Conscientiousness [increases steadily](http://www.researchgate.net/publication/227517515_Is_Character_Fate_or_Is_There_Hope_to_Change_My_Personality_Yet/file/9fcfd50770b918ab25.pdf "'Is Character Fate, or Is There Hope to Change My Personality Yet?', Edmonds et al 2008") over a lifetime (in contradistinction to IQ's [steady fall](DNB FAQ#aging)), which is a hopeful observation. I like how [Richard Hamming](!Wikipedia) put it in ["You and Your Research"](http://www.cs.virginia.edu/~robins/YouAndYourResearch.html):

> ...Now for the matter of drive. You observe that most great scientists have tremendous drive. I worked for ten years with John Tukey at Bell Labs. He had tremendous drive. One day about three or four years after I joined, I discovered that John Tukey was slightly younger than I was. John was a genius and I clearly was not. Well I went storming into Bode's office and said, "How can anybody my age know as much as John Tukey does?" He leaned back in his chair, put his hands behind his head, grinned slightly, and said, "You would be surprised Hamming, how much you would know if you worked as hard as he did that many years." I simply slunk out of the office!
>
> What Bode was saying was this: "Knowledge and productivity are like compound interest." Given two people of approximately the same ability and one person who works 10% more than the other, the latter will more than twice outproduce the former. The more you know, the more you learn; the more you learn, the more you can do; the more you can do, the more the opportunity - it is very much like compound interest. I don't want to give you a rate, but it is a very high rate. Given two people with exactly the same ability, the one person who manages day in and day out to get in one more hour of thinking will be tremendously more productive over a lifetime. I took Bode's remark to heart; I spent a good deal more of my time for some years trying to work a bit harder and I found, in fact, I could get more work done. I don't like to say it in front of my wife, but I did sort of neglect her sometimes; I needed to study. You have to neglect things if you intend to get what you want done. There's no question about this.

Or to quote some [_Harry Potter_ fanfiction](http://www.fanfiction.net/s/5782108/10/Harry_Potter_and_the_Methods_of_Rationality "'Harry Potter and the Methods of Rationality', by Eliezer Yudkowsky; chapter 10") instead:

> [Harry:] "Where would I go, if not Ravenclaw?"
>
> [Sorting Hat:] "Ahem. 'Smart kids in Ravenclaw, evil kids in Slytherin, wannabe heroes in Gryffindor, and everyone who does the actual work in Hufflepuff.' This indicates a certain amount of respect. You are well aware that Conscientiousness is just about as important as raw intelligence in determining life outcomes, you think you will be extremely loyal to your friends if you ever have some, you are not frightened by the expectation that your chosen scientific problems may take decades to solve..."

# Online education's factors

How does online education affect them - reducing the need for that factor to reach a certain level of attainment, leaving it alone, or increasing the need for that factor?

1. IQ seems like it could go any way:

    - Any effects could roughly cancel out, perhaps in some sort of compensating mechanism where students only aim at particular levels of mastery or performance and better or worse methods only change how much time they need to invest before they go off to play video games.
    - It could *increase* the need for IQ, because now all the extraneous time-wasting 'gunk' like sharpening pencils or doing roll-call can be cleared away by the technical solutions, leaving more time for pure learning. By eliminating all the environmental hindrances and variation, the only variation left will come from the student's innate intellectual abilities: IQ. Students will race through courses until they hit their natural limits; even Sal Khan's videos can't make a dim bulb calculate solutions to Schrodinger's equation.

        It has been noted in the psychometric literature that successful attempts to eliminate socio-economic penalties and provide quality environments for all children would necessarily *increase* the apparent contribution of heredity: if every child is in an environment that lets them develop and flourish to their fullest extent, then any remaining differences in their development will be due to hereditary factors! If variations in IQ are the joint product of variations in heredity and environment, then eliminating all variation in environment, setting environment to 0, means the remaining variation will be just the variation in heredity.
    - It could reduce the need for IQ, since online education will lead to a marketplace of lessons where only the clearest, most insightful, easily understood lessons survive. In ordinary classrooms staffed by ordinary teachers, extemporaneous lectures or explanations are necessarily more opaque and lower-quality compared to a lecture that the world-class presenter has spent months or years honing.

        But it is a utopian thought that perhaps everyone will be successful at education; so the question becomes, what trait or environmental factor would then become the best predictor of attainment? If you reduce the need for brains, then perhaps you still need motivation and appetite for work, which in conjunction with the previous point about joint products leads us to the next observations...
2. Conscientiousness is the joker. There is one clear possible change: online education will *increase* demand for Conscientiousness compared to offline education.

    This has been suggested on more than one occasion[^previous-art-1][^previous-art-2]. This tallies with my personal experience with online courses and classes with online assignment components like computer science classes (where class attendance may be optional and programming projects or homework are submitted remotely). I had a good deal of trouble just sitting down to do the course or assignment, even though it was not necessarily that difficult. The distractions on my laptop beckoned: I would go use crufty old Solaris boxes in the computer labs just to avoid the distractions and get something done. Other experiences were more dramatic: one CS exam was done on computers, with a built-in test suite you could run to get your exact grade, so one could spend hours working on it until one had a perfect 100 (which wasn't terribly hard), which of course I did - so I was shocked when the teacher showed us the grade distribution and it looked like a normal CS exam distribution, with plenty of <100 scores and outright failures!
3. Miscellaneous is too varied and heterogeneous to be predictable, so we won't discuss it further.

[^previous-art-1]: One might say it's the obvious challenge for distance/online learners, especially to anyone who has tried. Eg. [Coombs-Richardson 2007](http://cslsrv.ice.ntnu.edu.tw/LabNews/Minutes07F/20071106_%E8%95%AD%E8%B2%B4%E5%BE%BD_Personalizing%20Distance%20Learning.pdf "Personalizing Distance Learning"):

    > Personality types and learning styles also may affect student performance in distance learning. Participants with an extraverted personality type-who enjoy the physical interaction of working with others (Meisgeier and Richardson 1996)-may feel isolated from the human experience and become disillusioned. Considering learning styles, Elkins et al. (2002) found in a two-year study of Web-assisted courses that divergent learners-who seek broad elaborate ideas prompted by a problem or stimulus-did not perform nearly as well as convergent learners-who are able to bring material from a variety of sources to solve a problem...What does an online course demand that a face-to-face class does not? Online learning requires self-discipline and a greater amount of work than a face-to-face course. Students must demonstrate a high degree of autonomy and motivation (Ladyshewsky 2004).
    >
    > - Meisgeier, C., and R. C. Richardson. 1996. "Personality types of interns in alternative teacher certification programs". The Educational Forum 60(4): 350-60 TODO
    > - Elkins, V., C. Rafter, R. Eckart, E. Rutz, and C. Maltbie. 2002. "Investigating learning and technology using the MBTI and Kolb's LSI". Paper presented at the 2002 ASEE Annual Conference and Exposition, June 16-19, Montreal, Quebec, Canada.
    > - Ladyshewsky, R. 2004. ["Online learning versus face to face learning: What is the difference?"](http://www.ascilite.org.au/ajet/ajet20/ladyshewsky.html) Paper presented at the 2004 Teaching and Learning Forum, February 9-10, Murdoch University, Murdoch, Western Australia.
[^previous-art-2]: Coombs-Richardson 2007:

    > ...Successful distance learners share some distinctive features in their mode of study ([Littlefield 2005](http://distancelearn.about.com/od/isitforyou/a/considering.htm "Is Distance Learning Right for You? Find Out if You Have the Five Qualities of Successful Distance Learners")):
    >
    > - They work independently, are self-motivated and persistent, and do better without people giving them constant guidance.
    > - They seldom procrastinate, realizing that timelines are important and that neglecting to turn in their work on schedule may end up delaying completion of their studies.
    > - They demonstrate good reading and writing skills, which are essential for acquiring most of the course information. Though some distance learning courses offer video recordings and audio clips, these are not sufficient to master the competencies.
    > - They are able to remain on task in spite of relentless distractions, such as frequent interruptions while learning at home.

## Existing research

The general background of online education demonstrated in a large [DoE 2009 meta-analysis](http://www2.ed.gov/rschstat/eval/tech/evidence-based-practices/finalreport.pdf "'Evaluation of Evidence-Based Practices in Online Learning: A Meta-Analysis and Review of Online Learning Studies', Means et al") is that a lot of studies are poor or not randomized controlled trials (unsurprisingly) but in the quality studies, online learning slightly outperforms regular classes and mixed classes outperform both online & offline classes[^extras] (see also the similar results [Zhao et al 2005](http://ott.educ.msu.edu/literature/report.pdf "What makes the difference? A practical analysis of research on the effectiveness of distance education") & [Bowen et al 2012](http://mitcet.mit.edu/wp-content/uploads/2012/05/BowenReport-2012.pdf "Interactive Learning Online at Public Universities: Evidence from Randomized Trials")). The age of students doesn't seem to matter much although the meta-analysis seemed to see a shrinking effect going from undergraduate college students to professionals or postgraduates^[This might be evidence against: since Conscientiousness increases modestly with age/experience, we would expect older people (professional/post-grad) to benefit more than younger (undergrads). This may reflect differences in the kinds of subjects or the material - perhaps older people taking training are different from the studied undergrads or perhaps their more advanced/specialized material has not been pedagogically polished as more common undergrad material, etc.]. This meta-analytic result is broadly consistent with the picture previously painted: if we accept that online education should be better then a small increase in average scores is consistent with some students benefiting much more and some losing a little; the mixed classes, with their face-to-face elements, compensate for lacks in Conscientiousness, giving more students the best of both worlds; and independent study hurts results for the exact same reason.

[^extras]: In an interesting comment on the "possibilities" argument for online learning (that such courses can add material and media that offline courses cannot or will not), identity of courses turns out to be an important moderator:

    >  Studies in which analysts judged the curriculum and instruction to be identical or almost identical in online and face-to-face conditions had smaller effects than those studies where the two conditions varied in terms of multiple aspects of instruction (+0.13 compared with +0.40, respectively)...In many of the studies showing an advantage for blended learning, *the online and classroom conditions differed in terms of time spent, curriculum and pedagogy*. It was the *combination* of elements in the treatment conditions (which was likely to have included additional learning time and materials as well as additional opportunities for collaboration) that produced the observed learning advantages. At the same time, one should note that online learning is much more conducive to the expansion of learning time than is face-to-face instruction.

There is also some academic research directly examining personality factors, which compare online and offline performance and also collect personality data^[In studies which don't collect the necessary information on Conscientiousness, I believe it *may* be possible to observe this effect by looking at standard deviations in the scores: the online class should have a greater range, as the un-Conscientious flunk out by doing less while the Conscientious thrive on the optimized presentation. On the other hand, it could be that the online class has higher averages and similar standard deviations, and the un-Conscientious just tend to make up the lower half of the test scores, so standard deviations don't seem like a reliable indicator. Unfortunate, since there are many more studies simply comparing online and offline education than comparing them while also collecting personality data on subjects.]; I currently know of these relevant studies:

1. ["Procrastination in Online Courses: Performance and Attitudinal Differences"](/docs/conscientiousness/2003-elvers.pdf), Elvers et al 2003; result:

    > There were no reliable differences between the 2 sections of the class on the measures of procrastination, exam performance, or attitudes toward the class. Yet, procrastination was negatively related with exam scores and with attitudes toward the class for the online students, but not for the lecture students. This difference may partially explain why online courses designed to increase the educational efficacy of a course often show no difference in performance when compared to lecture classes.

    Background:

    > If procrastination is a problem in online classes, it would be desirable to know which students are most at risk for procrastination. Instructors could then offer the at-risk students interventions designed to reduce dilatory behaviors. Watson (2001) and Schouwenburg and Lay (1995) correlated self-reported procrastination with five factors of personality. Both found a reliable relation between self-reported procrastination and low conscientiousness. Watson found a reliable relation between procrastination and neuroticism. Schouwenburg and Lay also found some, but not all, facets of neuroticism to be related to procrastination.

    What did the students say and what difference was found in their scores?

    > One question asked in the end-of-semester questionnaire was whether the student disliked the class because it was easy to get behind in the class. In the online class, 19 of 21 students reported that they disliked the class because it was easy to get behind. Only 13 of 23 students in the lecture class reported that they disliked the class because it was easy to get behind...However, the magnitude of the relation between procrastination and class performance and attitudes seemed to be larger for the online class than for the traditional class. Procrastination was a good predictor of performance for each of the five tests in the class for the online students, but not a good predictor of performance for any of the five tests for the lecture students.

    Finally, the quote that really sums it all up:

    > Pedagogy suggests that activities such as online discussions, group writing projects, and immediate feedback on performance should lead to better performance. Thus, students in online classes, which often contain these activities, should have better performance in the class compared to traditional lecture classes, which often lack these activities. However, this is rarely the case. Russell (1999) cited more than 300 studies that failed to find any reliable difference in performance between traditional classes and classes at a distance (including correspondence courses, online courses, and telecourses). The observation that the magnitude of the relation between procrastination and exam scores was larger in this online class than in the lecture class could be a possible explanation for these null results. The additional activities in online classes that should increase performance may do just that. However, the decrements associated with dilatory behaviors in online classes may attenuate the increments associated with the additional activities. By reducing dilatory behaviors, the benefits of online classes may become more apparent.
2. Irani et al 2004, ["Personality type and its relationship to distance education students' course perceptions and performance"](/docs/conscientiousness/2004-irani.pdf): non-randomized case study using MBTI
2. Kim & Schniederjans 2004, ["The role of personality characteristics in web-based distance education courses"](/docs/conscientiousness/2004-kim.pdf): in its sample of 140 students, online education worked best for those high on the Wonderlic PCI Success Scales for 'Commitment to Work' ("The tendency to remain on a job for a long time, and not be undependable, irresponsible, impulsive, disorganized, or lack persistence.") and 'Learning Orientation' ("The tendency of an individual to be willing to engage in activities to acquire knowledge, skills, and behaviors and to learn new methods and procedures to improve job effectiveness, how interested they are in developing themselves, seek opportunities to learn new and different ways of doing things, and enrolled in training programs that they are likely to be active and fully engaged participants.") Unfortunately, these are not exactly equivalent to Conscientiousness.
3. Schniederjans & Kim 2005, ["Relationship of Student Undergraduate Achievement and Personality Characteristics in a Total Web-Based Environment: An Empirical Study"](/docs/conscientiousness/2005-schniederjans.pdf); similar to Kim & Schniederjans 2004, 260 students. It found Conscientiousness statistically-significant, but also 3 others (Openness, Neuroticism, and Openness) and not Extraversion. (Neither seems to include any effect size or whether Conscientiousness out-predicts the other factors; this may be due to my inability to interpret some of the provided statistics.)
4. Bassili 2006, ["Promotion and prevention orientations in the choice to attend lectures or watch them online"](http://weboption.utsc.utoronto.ca/sites/default/files/Student_Characteristics_in_JCAL_12_06.pdf) measured only Neuroticism and Openness, so cannot tell us anything about Conscientiousness.
5. Bishop-Clark et al 2007, ["The effects of personality type on web-based distance learning"](/docs/conscientiousness/2007-bishopclark.pdf); MBTI, unfortunately
6. Berenson et al 2008, ["Emotional Intelligence as a Predictor for Success in Online Learning"](http://www.irrodl.org/index.php/irrodl/article/viewArticle/385/1036); correlational study, collapses Conscientiousness with other items into a "persuasiveness" item which does correlate with higher online grades.
7. Bolliger & Avgerinou 2009, ["Student Satisfaction with Online Courses Based on Personality Type"](http://www.editlib.org/p/31835/proceeding_31835.pdf); just an abstract (and MBTI). More importantly, it's not clear we can learn anything from surveys of satisfaction or happiness or enjoyment: [Nemanich et al 2009](/docs/conscientiousness/2009-nemanich.pdf "Enhancing Knowledge Transfer in Classroom Versus Online Settings: The Interplay Among Instructor, Student, Content, and Context"), a quasi-experiment, found that in classrooms, higher enjoyment = higher scores, but that correlation was much weaker in their online setting
8. Avgerinou 2010, ["Teacher vs. student satisfaction with online learning experiences based on personality type"](http://web.archive.org/web/20121205035225/http://etpe.eu/files/proceedings/26/1286265424_4.pdf): MBTI, does not report detailed information.
9. Abzug 2010, ["E-conscientiousness and e-performance in online undergraduate management education"](/docs/conscientiousness/2010-abzug.pdf); did not measure Conscientiousness via standard questionnaire but via activity in the online course (a performance measure similar to that of [Hedengren & Stratmann 2012](http://papers.ssrn.com/sol3/papers.cfm?abstract_id=2194373 "The Dog that Didn't Bark: What Item Non-Response Shows about Cognitive and Non-Cognitive Ability")'s item non-response way of measuring Conscientiousness which seemed to correlate well with traditional questionnaires)
9. Chahino 2011, ["An exploration of personality type success in online classes"](/docs/conscientiousness/2011-chahino.pdf); uses [DISC assessment](!Wikipedia) (not Big Five or MBTI), finding no correlation with DISC results
10. [Mellish 2011](/docs/conscientiousness/2011-mellish.pdf "Personality type and success in an online learning environment"); correlational, using MBTI; 102 online students (83 female) were equally distributed among personality types (no offline control/comparison), no obvious personality correlation with performance
10. Varela et al 2012, ["Online learning in management education: an empirical study of the role of personality traits"](/docs/conscientiousness/2012-varela.pdf); quasi-experimental comparison of offline & online:

    > In testing H2, learning was regressed on conscientiousness. Results support the ability of conscientiousness to explain learning variance across groups (β=4.11, SE=1.41, _p_<.05). Then, learning was regressed on conscientiousness, initially, in the face-to-face sample and then, in the online group. While the regressor coefficient was not statistically-significant for the face-to-face group (β=3.49, SE=2.01, _p_>.05), the regression coefficient exhibits a stronger and [statistically-]significant effect size for the online group (β=4.59; SE=1.96, _p_<.05). Consistent with the expectations in H2, results corroborate that conscientiousness has a stronger ability to account for learning variance in online settings (R^2^=.079) than in face-to-face contexts (R^2^=.040).
11. Ellis & Howard 2012, ["The Effects of Gender and Dominant Mental Processes on Hypermedia Learning"](http://www.editlib.org/f/40481): MBTI, no offline
12. Yang et al 2012, ["The impact of social capital and personality traits on students' e-learning experience"](http://www.davidraska.com/David_Raska/Downloads/2012_Winter_Proceedings.pdf#page=325); no randomization or comparison group, notable mainly that in their online marketing class, "Contradictory to this common belief, our findings show that the conscientiousness trait does not influence students' e-learning experience. However, the social orientation trait does. Furthermore, this positive influence from the social orientation trait becomes stronger when larger social capital exists."
13. Punnoose 2012, ["Determinants of Intention to Use eLearning Based on the Technology Acceptance Model"](http://jite.informingscience.org/documents/Vol11/JITEv11p301-337Punnoose1197.pdf); masters degree Thai students, did not investigate any correlates of achievement but did find Conscientiousness had small correlations with attitudes towards the course.
14. Keller & Karau 2013, ["The importance of personality in students' perceptions of the online learning experience"](/docs/conscientiousness/2013-keller.pdf): "The current research examined the relationship between the Big Five personality dimensions and five specific types of online course impressions (engagement, value to career, overall evaluation, anxiety/frustration, and preference for online courses). Results revealed that conscientiousness was the most consistent predictor of an individual's impressions of online courses." They did not record any grades or exam scores.
15. Fariba 2013, ["Academic Performance Of Virtual Students Based On Their Personality Traits, Learning Styles And Psychological Well Being: A Prediction"](/docs/conscientiousness/2013-fariba.pdf); survey of self-selected online students which found large negative correlation between grades & Neuroticism, and smaller correlations with Conscientiousness/Extraversion/Openness.
16. Shih et al 2013, ["The Relationship Among Tertiary Level EFL Students' Personality, Online Learning Motivation And Online Learning Satisfaction"](http://ac.els-cdn.com/S1877042813038871/1-s2.0-S1877042813038871-main.pdf): "extraversion and conscientiousness were the two important traits among the Big Five in predicting motivation and satisfaction" (but no measure of grades or online/offline experimental design)
17. Santo, S.A.: "Virtual learning, personality, and learning styles". Dissertation Abstracts International Section A, Humanities & Social Sciences, 62, pp. 137 (2001)
18. Zobdeh-Asadi, S.: "Differences in personality factors and learners' preference for traditional versus online education". Dissertation Abstracts International Section A: Humanities & Social Sciences, 65(2-A), pp. 436 (2004)

# Factor changes

Now, we discarded #3 as being impossible to generalize about, and #2 suggests that Conscientiousness will increase in its correlation with success, while to me the more plausible outcome for #1 is that it will reduce the need. But to be conservative, let's assume the need for IQ remains unchanged. This suggests the following argument:

1. Material presented in an online education format: requires the same amount of IQ to understand[^better-material-limits]
2. Material presented in an online education format: also requires more Conscientiousness than the same material presented in a classroom
3. there are no other factors; *then*
4. less of the general population will be able to learn it.

[^better-material-limits]: One wonders how much hope can we place in the falsity of #1. Just how much *can* education's IQ requirements be brought down? Advocates seem optimistic, but is the current material all that bad? How dumb can you be before even the best highest-quality of calculus becomes unlearnable with feasible amounts of time and effort on your part? How close are existing online courses to this lower bound on IQ? At what point does #1 resume being true?

To belabor the obvious and dress it up in mathematical garb: for a particular static set/population Z, the number of Z members which satisfy the requirements  $IQ + C < IQ + (C+1)$, because the fraction of the population with both the necessary IQ and the necessary Conscientiousness must be equal to or smaller than the fraction with just the necessary IQ; for any properties $P(a \wedge b) \le P(a)$. See also the [conjunction fallacy](!Wikipedia). When it comes to normally distributed traits like IQ, modest selection pressure can drive down the fraction of eligible people to near-zero rates; for example, far less than 1% of the population will be 2 standard deviations above the mean on both IQ *and* Conscientiousness and this holds true even if we assume that both traits are highly correlated with each other (they're not), see the appendix for formulas & calculations.

(A major caveat here is that the premises really do need absolute values of IQ and Conscientiousness. If you only have correlations, I believe it is possible for IQ's correlation for educational success remain the same and Conscientiousness's correlation go up while the fraction of the general population succeeding goes up *also*. For example, if online education reduced the need for Conscientiousness, but reduced the need for IQ even more, more people will pass by the opposite of our conjunctive reasoning, but any attempt to predict success will benefit less from information about IQ than about Conscientiousness.)

Now, to discuss claim #2 in more detail. The first study cited previously on online education stressing Conscientiousness, Elvers 2003, is particularly interesting (see the quotes in the footnote). Now, given the evidence from this study that online education scores correlate with Conscientiousness, it seems very likely that #2 is true. However, the result that the online students had the same average as the offline students indicates that the conclusion #4 is not true; the obvious candidate to reject via modus tollens is assumption #1. As one would hope! But if #1 is not true, it could be true to a very large degree - as already mentioned, computerized education could make education a lot less correlated with your raw IQ because it's presented better or whatever (to listen to the most rapturous users of Khan Academy). However, the *equality* in scores between the online and offline classes indicates that whatever the drop in IQ requirements, it was offset by the increase in Conscientiousness requirements.

What does this tradeoff between loading on Conscientiousness and IQ suggest?

1. First, it suggests that blended learning will be intermediate in results: I'd expect partial online education to be 'weaker' than full online education in loading on Conscientiousness.

    You have to force yourself to go to class, but then it's still easier to learn without burdening your willpower/Conscientiousness. (You can always, say, not bring your laptop to class - difficult or impossible with online education!) I'd expect the effect of non-mandatory to be intermediate, much like I'd expect frequent mandatory deadlines in online education to help only a little.
2. Second, if one lone course shows such a hit from lack of Conscientiousness, what happens as ever more material goes online and students might be expected to do entire semesters just online?

    Will we see the correlation go up, as students expend all their willpower and run completely dry (see eg. Baumeister & Tierney 2010, [_Willpower_](http://www.amazon.com/Willpower-Rediscovering-Greatest-Human-Strength/dp/0143122231/))? (You may be able to lift 1 weight up to your head and do that 10 times in a row, but if given 10 weights simultaneously to lift, you'll drop them all.) It seems that the tradeoff might extend well beyond a single course to all courses.

# Consequences

Is loading outcome more on Conscientiousness a bad thing? I think it is, for a few reasons, some of which follow directly from the tradeoff and some of which are speculation about future consequences:

1. there is no particular reason to favor Conscientiousness as an additional reward for 'good' people. Whether we should favor it over IQ depends on the *consequences* such as what mental traits we need more of in our elites.

    Conscientiousness is not a 'virtue' in the sense that the (non-existent) homunculus in your brain is 'good' or 'bad' for choosing to be Conscientious or not, any more than it is morally laudable to be high IQ than low IQ. Despite [folk psychology & moralizing](http://medicalhypotheses.blogspot.com/2009_08_01_archive.html "Reliable but dumb, or smart but slapdash?"), the Big Five personality traits are stable over lifetimes like IQ, are turning out to be influenced by heredity like IQ, and progress is being made on tracing the traits to the underlying neurological factors like IQ. You can no more 'try hard to be able to try hard' (how circular) than you can try hard to be more intelligent.

    Even if we find that Conscientiousness is not affected or Conscientiousness does not correlate with any problematic traits like psychopathy, that doesn't exclude other personality traits: Varela et al 2012 finds that online performance was also correlated with being low on "gregariousness", a subfactor of Extraversion matching on "individuals who confine themselves from social settings" (rather than just being quiet and reserved in social settings) - is this a good, bad, or neutral thing, morally? Or practically?
2. As already observed, the school system already [rewards](http://medicalhypotheses.blogspot.com/2009/05/do-elite-us-colleges-choose-personality.html "Do elite US colleges choose personality over IQ?") Conscientious grinds, and [oppresses creativity](http://itari.in/categories/Creativity/19.pdf "'Creativity: Asset or burden in the classroom?', Westby & Dawson 1995"). Do we need to make the former even more true? Think of how this will penalize [bright creative potential-future-great-scientists](http://kernull.com/bioradio.pdf "Why are modern scientists so dull? How science selects for perseverance and sociability at the expense of intelligence and creativity") - but uninterested in forcing themselves to do mandated drudge-work - nerds. We have all heard stories of geniuses like [Einstein or Darwin or Jung](https://web.archive.org/web/20130106142316/http://www.pages.usherbrooke.ca/rviau/articles/principales_communication/eminent_scientists_demotivation_in_school.pdf "'Eminent Scientists' Demotivation in School: A symptom of an incurable disease?', Viau 2004") who despised lower or higher education, or did their best to ignore it while educating themselves - Simonton's 1994 [_Greatness: Who makes history and why_](http://www.amazon.com/Greatness-Who-Makes-History-Why/dp/0898622018/) estimates that this is not a few anecdotes but 60% of his sample. ([Conscientiousness is necessary](http://lesswrong.com/lw/9m6/the_personality_of_greatcreative_scientists_open/ "The Personality of (great/creative) Scientists: Open and Conscientious") for scientific greatness, but not *that* much.)

    If we stand idly by and let Conscientiousness shifts happen, saying that it must be a good thing since it is happening, I believe we are guilty of [status quo bias](!Wikipedia). A useful thought here is Bostrom's [reversal test](http://wiki.lesswrong.com/wiki/Reversal_test): why do we think that the current demands for Conscientiousness are optimal? Or the *double*-reversal test: suppose some alien or technology suddenly intervened in our educational system and made it load even more heavily on IQ but someone came up with a simple way to place burden back on Conscientiousness - would we accept their solution? I suspect in both cases, we would be unable to produce any good answer to this important issue.

    It's worth noting that a little appreciated property of the bell curve or normal distribution is that a very small shift in the average can have unintuitively large consequences at the tails: a shift of 1 IQ point in the general population can result in considerable changes in the population all the way out at, say, 160+ IQs. We can grasp this by looking at the [changes in rarity](!Wikipedia "Normal distribution#Standard deviation and tolerance intervals") by standard deviation: someone at 2 deviations is 1 in 22, 3 deviations 1 in 370, 4 = 1 in 15,787 (42x fewer than 3), and 5 = 1 in 1,744,277 (110x fewer than 4). A common standard deviation for particular IQ tests is 15 points, so 3 deviations out is ~145 IQ, which is around the observed minimum for great Nobel-winning scientific or mathematical work^[When this is mentioned, some wit often tries to bring up [Richard Feynman](!Wikipedia)'s supposed IQ score in the 130s; while this is obvious bunk (a case of ["one man's modus ponens is another man's modus tollens"](Prediction markets#modus-tollens-vs-modus-ponens)), [a closer look at the source](https://news.ycombinator.com/item?id=1251164) of the anecdote reveals many reasons why the score is either false or unreliable.]. This is interesting because some interventions like [iodization](!Wikipedia "Iodised salt") can have [shockingly large effects on IQ](Iodine) in the worst-off environments - such as an average increase of as much as 15 IQ points - which would suggest that if a hypothetical intervention moved a population a standard deviation from 85 to 100 IQ, its subpopulation at 145 goes from being 4 deviations away to 3 - which increases that subpopulation's ranks by 42x or 4200%![^Jensen] (One meta-analysis of iodine effects, Scrimshaw 1998, apparently did find a shift of the overall bell curve; and further, iodization benefits females more than males, so there may have been nontrivial consequences there...)

    The implications are obvious for any academic system that forced its membership's average IQ down a few points in exchange for researchers higher on Conscientiousness: it may have outsized effect on how much of its membership are the very smartest researchers around.
3. The tradeoff resulting in online education favoring Conscientiousness was neither designed in nor realized by the designers; it is purely accidental and undesired. Wouldn't it be extraordinary if an accidental tradeoff turned out to be exactly optimal? How very convenient!

    This is a good time to apply the [status-quo reversal test](http://wiki.lesswrong.com/wiki/Reversal_test): suppose online education did not result in any such tradeoff but a Khan Academy staffer unilaterally made some changes meant solely to make KA scores reflect Conscientiousness more (perhaps your progress would be deleted if you did not Conscientiously log in every week and do a few problems). Would you approve of this change? Suppose further online education actually reduced the need for Conscientiousness (maybe because the service pings your cellphone with a quick practice problem every so often); would you approve of the staffer's change then? If you would not approve in the latter scenario where the shift along the tradeoff curve is intentional, why would you approve of a shift caused accidentally?
4. The cheapness of online education may prove irresistible and a case of [worse is better](!Wikipedia): the cost of human teachers is nontrivial and may be increasing (whether this is due to backloaded pension compensation, growth of the education sector & diminishing returns, [Baumol's cost disease](!Wikipedia) etc.), and this has prompted reactions like the death of university tenure & wholesale use of adjuncts, attacks on unions, and interest in automated methods of teaching... like online education. Already cuts have begun. Even if online education is worse, there may be no choice about whether to use it or not - a sort of educational [enclosure](!Wikipedia) movement. This shift may or may not be economically efficient (if the public sector is able to force the losses onto the public which is not organized enough to avoid it, perhaps due to ideological divisions).
5. Economic growth is increasingly captured in the US by the most-educated, with income growth going mostly to graduate degree holders. So anything which may lessen the ranks of the most highly educated seems like it would exacerbate the inequality of returns to education. Is some general increases in the net wealth of the economy worth it? People do not eat absolute wealth increases, they eat relative increases - more egalitarian economies are happier populaces. (Note the same question can be asked of other 'cheaper' things like globalization and outsourcing, and the answer in those other cases is not trivial. [Pareto-efficient](!Wikipedia) does not mean everyone is better off, just that no one is worse off, and this assumes humans do not care about their rankings or place - a patently false approximation.)

[^Jensen]: [Arthur Jensen](!Wikipedia), [discussing the slight deviations](http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.138.980&rep=rep1&type=pdf "'How Much Can We Boost IQ and Scholastic Achievement?' 1969") from the bell curve in real-world populations at the extremes (<70 and >140) points out the consequence of shifting the means:

    > Examination of this normal curve can be instructive if one notes the consequences of shifting the total distribution up or down the IQ scale. The consequences of a give shift become more extreme out toward the "tails" of the distribution. For example, shifting the mean of the distribution from 100 down to 90 would put 50% instead of only 25% of the population below IQ 90; and it would put 9% instead of 2% below IQ 70. And in the upper tail of the distribution, of course, the consequences would be the reverse; instead of 25% above IQ 110, there would be only 9%, and so on. The point is that relatively small shifts in the mean of the IQ distribution can result in very large differences in the proportions of the population that fall into the very low or the very high ranges of intelligence. A 10 point downward shift in the mean, for example, would more than triple the percentage of mentally retarded (IQs below 70) in the population and would reduce the percentage of the intellectually "gifted" (IQs above 130) to less than one-sixth of their present number. It is in these tails of the normal distribution that differences become most conspicuous between various groups in the population that show mean IQ differences, for whatever reason, of only a few IQ points. From a knowledge of relatively slight mean differences between various social class and ethnic groups, for example, one can estimate quite closely the relatively large differences in their proportions in special classes for the educationally retarded and for the "gifted" and in the percentages of different groups receiving scholastic honors at graduation. It is simply a property of the normal distribution that the effects of group differences in the mean are greatly magnified in the different proportions of each group that we find as we move further out toward the upper or lower extremes of the distribution.
    >
    > I indicated previously that the distribution of intelligence is really not quite "normal," but show certain systematic departures from "normality." These departures from the normal distribution are shown in Figure 2 in a slightly exaggerated form to make them clear. The shaded area is the normal distribution; the heavy line indicates the actual distribution of IQs in the population. We note that there are more very low IQs than would be expected in a truly normal distribution and also there is an excess of IQs at the upper end of the scale. Note, too, the slight excess in the IQ range between about 70 and 90.
    >
    > ...The "excess" of IQs at the high end of the scale is certainly a substantial phenomenon, but it has not yet been adequately accounted for. In his multifactorial theory of the inheritance of intelligence, Burt (1958) has postulated major gene effects that make for exceptional intellectual abilities represented at the upper end of the scale, just as other major gene effects make for the subnormality found at the extreme lower end of the scale. One might also hypothesize that superior genotypes for intellectual development are pushed to still greater superiority in their phenotypic expression through interaction with the environment. Every recognition of superiority leads to its greater cultivation and encouragement by the individual's social environment. This influence is keenly evident in the developmental histories of persons who have achieved exceptional eminence (Goertzel & Goertzel, 1962). Still another possible explanation of the upper-end "excess" lies in the effects of [assortative mating](!Wikipedia) in the population, meaning the tendency for "like to marry like." If the degree of resemblance in intelligence between parents in the upper half of the IQ distribution were [substantially] greater than the degree of resemblance of parents in the below average range, genetic theory would predict the relative elongation of the upper tail of the distribution. This explanation, however, must remain speculative until we have more definite evidence of whether there is differential assortative mating in different regions of the IQ distribution.
    >
    > ...The reason is simply that assortative mating increases the genetic variance in the population. By itself this will not affect the mean of the trait in the population, but it will have a great effect on the proportion of the population falling in the upper and lower tails of the distribution. Under present conditions, with an assortative mating coefficient of about .60, the standard deviation of IQs is 15 points. If assortative mating for intelligence were reduced to zero, the standard deviation of IQs would fall to 12.9. The consequences of this reduction in the standard deviation would be most evident at the extremes of the intelligence distribution. For example, assuming a normal distribution if IQs and the present standard deviation of 15, the frequency (per million) of persons above IQ 130 is 22,750. Without assortative mating the frequency of IQs over 130 would fall to 9,900, or only 43.5% of the present frequency. For IQs above 145, the frequency (per million) is 1,350 and with no assortative mating would fall to 241, or 17.9% of the present frequency. And there are now approximately 20 times as many persons above an IQ of 160 as we would find if there were no assortative mating for intelligence.^3^

What other consequences may there be?

> This prodigious event is still on its way, still wandering; it has not yet reached the ears of men. Lightning and thunder require time, the light of the stars requires time, deeds, though done, still require time to be seen and heard. This deed is still more distant from them than the most distant stars - and yet they have done it themselves.

## External links

- [Original discussion on Google+](https://plus.google.com/103530621949492999968/posts/aKa3qLatwZ3)
- [LessWrong request for refs](http://lesswrong.com/lw/ac4/online_education_and_conscientiousness/)
- [Hacker News discussion](https://news.ycombinator.com/item?id=6476554)

# Appendices
## Selection on multiple normally distributed traits
### Simple questions

Suppose an elite university like Harvard decided to set a new admissions standard: they will only admit people who are 2 standard deviations above the mean on both IQ and Conscientiousness. If the filter is for 2 standard deviations above the mean and the variables are correlated with 1 (identical), then 2.3% of the population will pass; if the variables are uncorrelated with 0, then 2.3% of 2.3% (or 0.000529%) of the population will pass.

### Correlated

But what about intermediate values? For example, the psychology literature has reported a correlation of -0.21 between Conscientiousness & IQ, so we would expect an even tinier fraction of the population to pass, but what if we were optimistic and thought there was a positive correlation?

I consulted [Wikipedia on bivariate normal distributions](https://en.wikipedia.org/wiki/Multivariate_normal_distribution), but I didn't understand much of it. The closest I found was [sum of correlated normal random variables](http://en.wikipedia.org/wiki/Sum_of_normally_distributed_random_variables#Correlated_random_variables), but in this case what I want is closer to a `min` function.

#### Simulation

I was able to work up a R simulation to see how that worked, and it seemed in line with my intuitions:

~~~{.R}
# install.packages("fMultivar")
library ("fMultivar")

x <- rnorm2d(10000000, rho=0.5)

xgreater <- length(subset(x, x[,1] > mean(x[,1])+2*sd(x[,1])))
xandygreater <- length(subset(x, x[,1] > mean(x[,1])+2*sd(x[,1]) & x[,2] > mean(x[,2])+2*sd(x[,2])))

c(xgreater, xandygreater); c(xgreater / length(x), xandygreater / length(x), xgreater / xandygreater) * 100

# example results for different values of 'rho='
0.1
[1] 454,664  17,570
[1] 2.273e+00 8.785e-02 2.588e+03

0.2
[1] 458,284  82,552
[1]   2.2914   0.4128 555.1458

0.5
[1] 454,484  80,872
[1]   2.2724   0.4044 561.9794

0.9
[1] 455,242 267,912
[1]   2.276   1.340 169.922

0.95
[1] 455,162 321,024
[1]   2.276   1.605 141.784

0.99
[1] 455,260 394,448
[1]   2.276   1.972 115.417
~~~

#### Exact calculation
##### Bivariate min

I really was hoping for more of a precise analytic solution, so some more searching eventually turned up a paper, ["Exact Distribution of the Max/Min of Two Gaussian Random Variables"](/docs/conscientiousness/2008-nadarajah.pdf "Nadarajah & Kotz 2008"), which gives a definition for the min of 2 correlated normal variables. This seems to be what I want; top of pg1, second column:

> ...where $\phi(.)$ and $\Phi(.)$ are, respectively, the pdf and the cumulative distribution function (cdf) of the standard normal distribution. It is known that the [pdf](!Wikipedia "Probability density function") of $Y = \min(X_1, X_2)$ is $f(y) = f_1(y) + f_2(y)$, where
>
> (3) $f_1(y) = \frac{1}{\sigma_1} \phi (\frac{y-\mu_1}{\sigma_1}) \times \Phi (\frac{p(y - \mu_1)}{\sigma_1 \sqrt{1 - p^2}} - \frac{y - \mu_2}{\sigma_2 \sqrt{1 - p^2}})$
> (4) $f_2(y) = \frac{1}{\sigma_2} \phi (\frac{y-\mu_2}{\sigma_2}) \times \Phi (\frac{p(y - \mu_2)}{\sigma_2 \sqrt{1 - p^2}} - \frac{y - \mu_1}{\sigma_1 \sqrt{1 - p^2}})$

They give an R implementation on pg6 (first column); it seems to have a `pnorm` typo, but I fixed that. Once it was working, I tried generating a slightly (0.1) correlated bivariate distribution, which look OK:

~~~{.R}
fmin <- function (y,mu1,mu2,sigma1,sigma2,rho)
     {t1<-dnorm(y,mean=mu1,sd=sigma1)
     tt<-rho*(y-mu1)/(sigma1*sqrt(1-rho*rho))
     tt<-tt-(y-mu2)/(sigma2*sqrt(1-rho*rho))
     t1<-t1*pnorm(tt)
     t2<-dnorm(y,mean=mu2,sd=sigma2)
     tt<-rho*(y-mu2)/(sigma2*sqrt(1-rho*rho))
     tt<-tt-(y-mu1)/(sigma1*sqrt(1-rho*rho))
     t2<-t2*pnorm(tt)
     return(t1+t2)}

fmin(c(1:200),100,100,15,15,0.1)
  [1] 1.849e-11 2.864e-11 4.418e-11 6.784e-11 1.037e-10 1.578e-10 2.392e-10 3.608e-10 5.418e-10
  ...
~~~

Now, I understand the PDF to be "a function that describes the relative likelihood for this random variable to take on a given value. The probability for the random variable to fall within a particular region is given by the integral of this variable's density over the region". So I suppose I should sum up every point in the pdf >130 (since 130 is 2 standard deviations up, by construction when I specified SD=15) and that's my probability that a random deviate will be `min(130,130)`. What's the total probability someone will be over 130 on both variables? I think that would be:

~~~{.R}
sum(fmin(c(1:200),100,100,15,15,0.1)[130:200])
[1] 0.001004
~~~

If I increase the _r_ to 0.9, the result is 0.01455 which is satisfyingly larger.

A sanity check - as the correlation goes to 1.0, there should be no decrease. So we do the same question for a single normal distribution defined the same way:

~~~{.R}
sum(dnorm(c(1:200), 100, 15)[130:200])
[1] 0.02459

# the function blows NaN chunks on 1.0, so we'll try a lot of 9s:
sum(fmin(c(1:200),100,100,15,15,0.9999999999)[130:200])
[1] 0.02459
~~~

##### Bivariate double integral

An acquaintance gave me a double-integral formula:

$\int_2^\infty \int_2^\infty \frac{1}{2\pi\sqrt{1-\rho^2}}\exp\left (-\frac{1}{2(1-\rho^2)}\left [ x^2 + y^2 - 2\rho x y \right ] \right ) dx dy$

To calculate our 2-standard deviation minimum bivariate problem with a _r_=0.9 in R:

~~~{.R}
llim <- 2
ulim <- Inf
rho <- 0.9

f <- function(x,y) {
    (1 / (2 * pi * sqrt(1 - rho^2))) * exp(-(1 / (2 * (1 - rho^2))) * (x^2 + y^2 - 2 * rho * x * y))
}

# double-integration
integrate(function(y) {
   sapply(y, function(y) {
     integrate(function(x) f(x,y), llim, ulim)$value
   })
 }, llim, ulim)

0.01336 with absolute error < 1.6e-05
~~~

In Python using [SciPy](!Wikipedia):

~~~{.Python}
from numpy import *;
from scipy.integrate import *;

from matplotlib.pyplot import *;

def func(x, y, rho):
        return 1.0/(2.0*pi*sqrt(1.0-rho**2.0)) * exp(-0.5/(1.0-rho**2.0) * (x**2.0 + y**2.0 - 2.0*rho*x*y))

def answer(rho):
        return dblquad(func, 2, 100, lambda x: 2, lambda x: 100, args=(rho,))[0]

x = arange(-0.99, 0.99, 0.1)
y = zeros(len(x))
for i in range(len(x)):
        y[i] = answer(x[i])
        print x[i], y[i]

plot(x, y)
show()
~~~

###### _Monster_

Incidentally, we could also use this code for more frivolous purposes; for example, the critically-regarded manga [_Monster_](!Wikipedia "Monster (manga)") centers around two fraternal twins, one a psychopathic genius, and one might wonder how frequently pairs of fraternal twins come as pairs of geniuses (~3 standard deviations up) given that the fraternal correlations _r_=[0.5](!Wikipedia "Heritability of IQ#Correlations between IQ and degree of genetic relatedness")-[0.7](http://online.sfsu.edu/psych200/unit7/76.htm "MODULE 6: Effects of Heredity and Environment on individual Differences ")? We modify the R parameters:

~~~{.R}
llim <- 3
ulim <- Inf
rho <- 0.6
...
0.0001397 with absolute error < 3.4e-05
~~~

Twins in general make up 1-2% of the population, so one can tack another two zeroes to get an estimate of genius twins as being 0.0001397% of the global population or ~9,779 ($7000000000 \times 0.0001397 \times 0.01$); this is a bit of an underestimate since identical twins have much higher correlations like _r_=0.86, but could also be an overestimate since twins may have [IQs lower](http://www.bmj.com/content/331/7528/1306 "'The cognitive cost of being a twin: evidence from comparisons within families in the Aberdeen children of the 1950s cohort study', Ronalds et al 2005") by a third of a standard deviation (although [not all studies](http://www.bmj.com/content/333/7578/1095 "'Comparison of academic performance of twins and singletons in adolescence: follow-up study', Christensen et al 2006") are consistent) and this implicitly assumes a global average IQ of 100 (actual mean is more like 89). Finally, how many of those ~9,779 might we expect to be [psychopathic](!Wikipedia)? The correlation between IQ and psychopathy has [been found](!Wikipedia "Psychopathy#Learning impairment") to be weakly positive, non-correlated, or weakly negative (once selection effects like imprisonment are dealt with), for no apparent correlation; so we can simply multiply the 9,779 against the estimated population prevalence of ~1% for a final estimate of 98 genius psychopathic twins worldwide. (What fraction of those twins that might be raised in abusive orphanages and go on to star in manga is impossible to estimate.)

<!-- Higher ability trainees benefit more from self-paced individualized
instruction while lower ability trainees benefit more from group-paced classroom
instruction (Berkebile , 1975).
"Public education in heart-lung resuscitation: evaluation of three self-training methods in teenagers"
maybe contact KA about including a short big five? via jpulgarin?
-->
<!--
http://www.talentigniter.com/content/gender-differences-eligibility-gifted-programs
> This pool of kids is eligible for further screening on out-of-level tests, where students in the 5th through the 8th grade ages are allowed to take SATs and similar tests that are normed for older college-bound students. What we see is that there are more males at the very highest end. In the 1970s, the ratio for quantitative reasoning was 13 to 1 male to female. But in recent years, that gap has been closed to 4 to 1. However, experts in the academic intelligence field speculate that this is due less to a true gap closing than it is to a refocusing on girls and underrepresented minority math instruction while neglecting the needs of the highest ability math boys.
>
> So why do more girls get into the gifted programs? This has a lot to do with other factors, including differences in behavior, interests, energy levels, flexibility, brain growth and brain structure between boys and girls.
>
> In the structure of the brain, the part that interconnects the two hemispheres - the corpus callosum - is on average about 25% smaller in males than in females. This seems to lead to males thinking more in their left hemispheres while females think across and back and forth with both. As a result, more males tend to specialize and focus on what interests them. Gifted females tend to be high-level generalists and multi-taskers, natural managers.
>
> At school, the gifted girl looks around, notices she already knows everything, and uses it to her advantage. She can do it quickly and perfectly, her parents and teachers think she is great and give her lots of positive feedback, and she uses the time she's saved to run the school. The girl doesn't generally get into any trouble by behaving this way. So yes, of course, teachers are happy to recommend her for the gifted program.
>
> But with gifted boys, fewer of them like school compared to gifted girls. Fewer gifted boys show compliant behavior in school than gifted girls. Fewer gifted boys care about pleasing their teacher. Boys are less flexible in their interests than girls due to the structure of their brain, which, as previously stated, is more compartmentalized and linear than a female brain. As a result, boys may appear unmotivated in school.


For example, one of the '70s datasets OP alludes to is probably the SMPY gifted youth study; a quick ref is [Gender differences among talented adolescents](http://eec.edc.org/cwis_docs/NEWS_ARTICLES_JOURNALS/Lubinksi_current_dirs.pdf), Brody et al 1994; where _n_=~1m 7th/8th graders:

> In mathematically gifted samples, disparate male/female  proportions are well-known...The following proportions of males to females at various cutting score was approximately as follows:
>
> - SAT-M[ath] >= 500: 2/1
> - SAT-M >= 600, 4/1
> - SAT-M >= 700, 13/1

(Worth noting that this overrepresentation isn't true of verbal or fluid intelligence - it seems to be purely spatial/mathematical. So 'more smart men than women' is a little misleading.)

> It sounds to me like you're saying that the average is about the same between girls and guys, but that the standard deviation is higher for guys. is that right?

It probably is, and such a theory seems to [work nicely](http://www.lagriffedulion.f2s.com/math.htm), but it's still dangerous to say. Look at [Lawrence Summers](https://en.wikipedia.org/wiki/Lawrence_Summers#Differences_between_the_sexes).

Cowen -make your own economy-

When I think about my personal role in education, as an instructor, I sometimes wonder: Why do my students need *me*? Why can't they listen to someone else? They don't have to fly to Harvard or MIT, they just need a DVD player and an internet connection. Maybe an iPhone would do.
Let's say for instance that Greg Mankiw and recent Nobel laureate Paul Krugman are two of the sharper economic minds of the last few decades. It's not hard to record their lectures on DVD and sell them. I'm just not the most eloquent economist out there. Since many professors are giving those lectures anyway, it can't cost so much extra to record them and perhaps to reproduce their lecture notes as well. Note that both Mankiw and Krugman have written very successful principles-of-economics textbooks, so clearly they are willing to put time into popular education if the remuneration is there and perhaps even for free (both have had doctoral students, which is in essence an unpaid form of volunteer work).
The Teaching Company makes high-quality tapes of lectures by outstanding professors. It's a fine company and they offer some excellent products, but they're not a competitive threat to higher education in this country. If anything, I suspect the company boosts the hold of higher education by making more people aspire to greater knowledge, thereby increasing the long-run demand for in-person instruction. It is interesting that the demand for top colleges, and the price of college tuition, has taken off at exactly the same time as the internet revolution. I'm not suggesting that the spread of the internet caused this boom in quality higher education, but it does indicate the internet will not displace such education.
And if taping lectures seems too hard, or perhaps the rights are difficult to negotiate, how about just sitting at home and reading the textbook? (Heaven forbid.) Most people in college can read faster than they can listen to someone else speak.
You might think that a conspiracy of colleges and universities is stopping DVD-based or web-based instruction from spreading, but I find that hard to believe. There aren't many restrictions on what can be put on YouTube or what can be marketed on disc. The main problem is that if you received such an education, the so-called real world-most of all employers-wouldn't much respect it. Just try putting on your vita "Watched YouTube lectures for four years" and see how far you get. Listing the videos wouldn't much help you, no matter how good the list might look on paper. The real world is the constraint, not some monopolistic cabal in the upper reaches of higher education.
The reality is that most education requires the physical presence of other human beings. The flesh-and-blood instructor motivates students better and the presence of other students in the classroom makes the experience more vivid and memorable. Our proximity to both the leader (the professor) and the peers (the fellow students) means that we end up more interested, more focused, and more able to succeed in later life. As human beings most of us (but not all of us) are biologically programmed to respond positively to face time with others.
I call it *education as theater*. And it is not a one-man or one-woman show. Education as theater may be highly inefficient compared to some ideal of how we might absorb knowledge, but for most people it seems like the best we can do.
I've tried lecturing to an empty hall for the purposes of the recording camera. It's very hard to summon up the same enthusiasm and to make the stories memorable or funny without an admiring crowd. The point isn't that getting good tapes is impossible (put a real crowd in and tape the lecture), but rather that interpersonal connection is so often what motivates. If that is how the already-educated professor responds to the empty room, the indifferent reactions of a student to an empty room will be an even bigger problem.
We love the internet but when we go online we pursue our very personal agendas and interests and we spend most of our time connecting with other people. It's the very fun of that process that makes it so hard to master the derivation of income elasticity in Greg Mankiw's [_Principles of Economics_](http://www.amazon.com/Principles-Economics-N-Gregory-Mankiw/dp/0030259517/) text. There's always something better to do. Even when our friends are all away or at work, isn't the distraction of the internet ever-present? Not that many people go web cruising to spend their time on dry lesson plans. So schools use face-to-face education to connect the idea of income elasticity with a human personality and a human presentation.


One good approach to understanding the costs and benefits of story-based reasoning is to start with . . . a story.
In 1984 Thomas C. Schelling published a fascinating yet neglected article called "The Mind as a Consuming Organ." Schelling is a former Harvard professor and a Nobel laureate in economics. Schelling won the Nobel Prize for his analysis of strategic behavior and game theory, especially as he applied those ideas to military conflict and nuclear deterrence, and he finds most of his readers in those areas. "The Mind as a Consuming Organ" was never published in a professional refereed journal and if anything it has attracted more attention from political scientists. Nonetheless it's Schelling at his best.
...The interesting thing is, Schelling usually presents his ideas in terms of stories. This is unusual in a profession obsessed with mathematics and formal modeling. No matter what you say to him, Tom will start thinking about which kind of story might be relevant for formulating an insightful response. And once he starts narrating, he gets a dreamy look in his eye and no one wants to interrupt. The interjections and qualifications to the story are often as good as the main narrative itself.

The essay "The Mind as a Consuming Organ," as usual, draws upon Schelling's personal musings. How many other economists start their essays with a sentence like "Lassie died one night"? Here's the whole opening:Lassie died one night. Millions of viewers, not all of them children, grieved. At least, they shed tears. Except for the youngest, the mourners knew that Lassie didn't really exist. Whatever that means. Perhaps with their left hemispheres they could articulate that they had been watching a trained dog and that *that* dog was still alive, healthy, and rich; meanwhile in their right hemispheres, or some such place (if these phenomena have a place), the real Lassie had died.
Did they enjoy the episode?
Schelling emphasizes that we "consume" stories through memories, anticipations, fantasies, and daydreams. Concrete goods and services, such as Lassie programs, help impose order and discipline on our fantasies and give us stronger and more coherent mental lives.
... Consuming stories is not just a sideshow to the broader economic problem but rather it is one of the central human passions and one of the central sources of our well-being, including our satisfaction as consumers.
You're not just buying a sneaker, you're buying an image of athleticism and an associated story about yourself. It's not just an indie pop song, it is your sense of identity as the listener and owner of the music. If you give to Oxfam, yes you want to help people, but you also are constructing a narrative about your place in the broader world and the responsibilities you have chosen to assume.
The Portuguese author Fernando Pessoa wrote: "The buyers of useless things are wiser than is commonly supposed-they buy little dreams." That is a big part of what markets are about. Whether you are buying cosmetics, a lottery ticket, or an oil painting, you are constructing, defining, and memorializing your dreams into vivid and physically real forms. Gabriel García Márquez, in his Living to Tell the Tale (Vivir Para Contarla so "Living in Order to Tell It" is arguably a better or at least a more literal translation), understood the power of stories. His opening quotation notes: "Life is not what one lived, but what one remembers and how one remembers it in order to recount it."
...But aren't stories really just fantasy and isn't just "living in your head," when you get right down to it, simply bad? There is a fundamental criticism that must be addressed.
The criticism comes from Robert Nozick, the former Harvard philosopher, who provided what is considered the strongest and most potent critique of stories and fantasy. Nozick was an especially imaginative man and like so many other philosophers he wanted to convince us that there is something special about authenticity. (Recall Heidegger, or for that matter Sartre's Nausea: "But you have to choose: to live or to recount.") Toward that end, he poses what has now become a famous philosophical challenge, namely that of the experience machine, which he outlined in his 1974 book Anarchy, State, and Utopia.
The experience machine, as Nozick called it, offers the promise of experiencing whatever we want to. We could live our lives as heroes, have a hundred beautiful boyfriends or girlfriends, cure all of the world's diseases, or be the world's richest or most athletic man. It's a bit like the movie Total Recall except there is no malfunction and no evil corporation lurking in the background. It's just us and the pure fulfillment of all of our dearest dreams. You just have to plug into the machine, and of course the catch is that none of these experienced events are real. Once you are plugged in you think they are real (but only if you want to); in reality you are in a stinky room, lying on a dirty cot and hooked up to an ugly machine. Maybe there's a worm crawling up your leg or maybe you're in a clean, white hospital bed. You'll never know.
Nozick claims that most of us will reject such a fate, even though it provides us with some extraordinary mental experiences. For Nozick the rejection of the experience machine establishes a few philosophical points. First, we want to be certain kinds of persons, not just receptacles of happiness. Second, we value the truth or the authenticity of an experience. Third, hedonism cannot be the only or primary value because if it was we would all plug into the machine. Fourth, the meaning of humanity can't just be all about "living in our heads."
But I'm not quite convinced by Nozick's critique, even though I largely agree with the four points listed immediately above. Perhaps my skepticism stems from my background as an economist and my profession's emphasis on "choice at the margin," to cite that theme again. The choice is not "Fantasy: yes or no?" but rather "How much fantasy do we want in our lives?"
I've decided to plug into an experience machine, or at least not to unplug, and that machine is the human mind. It's pretty well established that our minds shape and frame truth as much as track it and few people would want, upon reflection, to live a life unadorned by the power of framing effects. We use framing effects all the time to make our experiences more vivid and more intense. Nor would most people, upon reflection, want a life without self-deception. If we were truly aware, all the time, of all the world's suffering, and more importantly aware fully of our own mediocrities (not to mention our inevitable death), many of us wouldn't be so happy. And as I've argued in my previous book, Discover Your Inner Economist, beneficial self-deception is common in human life, especially in marriage and career ambition. A lot of human achievement takes place only because we tell ourselves-often contrary to reason-that we are in fact smarter or wiser or better than other people.
In other words, we are all-now-allowing deliberately false movies to play through our heads and in part we let this happen so that we are happier and more successful. So for me the question is not whether to plug into or not plug into a machine, but rather how much to plug in and to what kind of machine. No one is choosing to opt for pure authenticity-whatever you might think that means-so let's not set up pure fantasy on the other side of the equation. It's all about choosing the right margin (again, that term from economics) of reality and fantasy, or to put it another way, I don't think the so-called real world is very "authentic" at all. No one who refuses to plug into the machine is in fact choosing or defending pure authenticity.

An issue arises if you get "too good" at finding the order in music. You must resort to bigger and bigger doses of informational complexity to achieve the prior effects that were so enjoyable. It's a bit like needing successively stronger doses of heroin, wanting to move beyond Vivaldi, or more prosaically having to switch from one pop song to the next. Don't we all do that? But the metric for the right amount of complexity differs across listeners, even across listeners with the same degree of musical experience and education.
The kid who listens only to Top 40 might feel that your love for Mahler is overly intellectualized, when for you Mahler is joy and pathos. I swooned over the Beethoven symphonies as a youth but today that's not enough for me. I get a visceral and electrifying surge from, say, a live performance by the Master Musicians of Jajouka, a micro-tonal noise band from rural Morocco that probably would hurt your ears. Live Indian classical music, especially of the percussive variety (Zakir Hussain is a special favorite) is for me also an emotionally ecstatic experience. Indian classical music, which does not rely so heavily on all-too-predictable harmonies, produces for me more excitement and raw emotion. Some people may need a more violent "feel" to their music, just as Kiriana Cowansage likes pictures and stories with lots of contrast and sharp relief. Atonal music, with its lack of traditional harmony and melody, often sounds brutal and discordant, as does the noise band from Morocco, and that is part of what I like about it.

I was curious and I asked Kiriana Cowansage what role music played in her life. Her answer, as you might expect, reflects the diversity of individual taste:I listen to music - usually only one or two songs on repeat for a month or more. Then I spontaneously get bored and switch. Usually, for about a week after such a switch, the new song makes me feel loopy and euphoric - I can't focus on any other activity - so I have to break in new songs for a period of time before I can use them as background. I have a similar reaction (face heating up, euphoria) to certain fast-paced rhythms and parts that crescendo or mount. In orchestral music, I like dark and rhythmic pieces, for example, Dance of the Knights. Despite this, I've never developed a real interest in music, beyond the listening part. I don't follow any particular artists and I don't have a favorite. In fact, I often can't name the song that I've been listening to for a month. I seem to latch onto internal elements of a song without caring about it as a whole or the artist in general.
A lot of what we don't like, in the arts, is simply creative forms that appeal to different and perhaps unusual neurologies. I am not saying that all people with unusual neurologies love atonal music or for that matter even know much about atonal music. It's just that if I go to a concert of contemporary classical music - the scratchy kind - I expect to see people with rather specialized cognitive skills, including the ability to order sounds that can easily seem chaotic into a comprehensible hierarchy.
Atonal and serialist music represent further signs of the division of productive labor present in all economically advanced societies. The world has become so wealthy and so diverse that some composers make music that appeals to people only with a very particular and very refine sense of musical appreciation. That's the best way to think about much of the music - and other art forms - that you may hate.
As with atonal music, the most common reaction is simply to evaluate the aesthetic perspective through the taste of either the public or the educated critics. We privilege those perspectives either because they have social status or because, in the case of the consumers, they have buying power and thus they command the attention of the media. So if it is serial killer stories, maybe the critics call it too lowbrow and talk about the decline of our society. If it is atonal music, it gets labeled as too inaccessible or too highbrow or it is claimed that the academic composers are perverse and self-indulgent. Most cultural criticism is staggering in how much it begs the question of what is the appropriate middle ground.
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<!-- ["Morningness-eveningness and educational outcomes: The lark has an advantage over the owl at high school"](/docs/melatonin/2013-preckel.pdf), Preckel et al 2013:
Individuals' cognitive ability has been examined in a plethora of studies and has been shown to be one of the best single predictors of academic attainment (e.g., Deary, Strand, Smith, & Fernandes, 2007; Mayes, Calhoun, Bixler, & Zimmerman, 2009). Meta-analysis by Fraser, Walberg, Welch, and Hattie (1987) revealed a correlation of .71 between IQ and academic performance. In a more recent meta-analysis, Strenze (2007) found a corrected correlation between IQ and academic performance (GPA) of .56 (see also Kuncel, Hezlett, & Ones, 2004).
Another well-investigated predictor of academic performance is conscientiousness, which represents one of the five factors of the Big Five model of personality (Goldberg, 1993) and which is described by such traits as being reliable, hardworking, self-disciplined, and persevering. The link between academic performance and conscientiousness has been examined in several studies (e.g., Furnham & Monsen, 2009; MacCann, Duckworth, & Roberts, 2009; Noftle & Robins, 2007; Preckel, Holling, & Vock, 2006). In a recent meta-analysis (Poropat, 2009), conscientiousness was confirmed as the strongest Big Five predictor of academic performance, faring better in some samples than intelligence (corrected r = .22).
-->

<!-- Russ: You also have a lot to say about conscientiousness and advantages that women might have over men. Explain. Guest: Well, one thing we are going to get very good at in the future--you see it now--is just measuring quality. So, whether it's doctors, lawyers, economics professors, there's always a randomized control trial now; there are always numerical ratings. Everything has a Yelp rating or an Amazon rating or something. And we all know these are highly imperfect but basically they are still better than not being informed at all. So it's like in the future there's a credit score for everything. So people who test well young I think will have a lot more invested in them early in their lives, early in their careers; and they'll have a head start. And another way to think of this is, I think, within 5 years the world's best education will be available online and it will be free. Arguably that's already the case. But the question is: Who is there to learn from this? It's the people who are disciplined and conscientious, which is still distinct from just raw intelligence. Now, if you ask the question if you compare men to women on average which group is less conscientious, I think you have to hand that one to the men. At least the lower tail of the distribution. So I think we already see in higher education and many other areas women doing better. And not just better because there is less prejudice. They are just outright doing better and out-competing the men. And I think that trend will be magnified by this increase value for conscientiousness. Russ: Explain again why conscientiousness is going to be more important then than it is now? Guest: There will be many more free resources; and there's already a lot. So the person who is just disciplined enough to sit down and, say, listen to EconTalk podcasts or read blogs or go through Kahn Academy or whatever it is they ought to be doing, that will be there for them free. So, what you'd call the 'shadow value' of conscientiousness in economic terms will be much, much higher. And you see that--students in India, they take Coursera classes and they are brilliant; but they are also really determined to work hard. And they are outperforming in general a lot of these top Stanford students. And that's being measured and picked up. And those people I think will do very well in this new water[?], and that's again a case of conscientiousness paying off. Russ: I guess it's not just the advantage of being disciplined to sit in front of the computer on your own time, but it's also the fact that possibly it will be harder to get somebody to be drilling you and pushing you face to face. Guest: That's right, especially for people with lower incomes.
http://www.econtalk.org/archives/2013/09/tyler_cowen_on.html -->
<!-- "The Importance of personality, IQ, and learning approaches: predicting academic performance" Rosander 2012 TODO: the URL? Study I & II, found Conscientiousness to be a correlate & predictor (respectively) -->