Exploratory Data Analysis and Visualization for Predicting Relative Political Lean for 2022 State Legislative districts
This project aims to produce Partisan Voter Index(PVI) metrics for the upper and lower Texas State Legislatures, and see if there is meaningful difference in metrics calculated using national election data vs state-wide election data.
Presentation Slides for this project can be found here.
The Cook Political Report's Partisan Voter Index (CPVI) is a measure of how strongly a state or congressional district leans towards the Republican or Democratic party, compared to the country as a whole.
It is a relative measure of lean for answering the question "How does this district vote?"
Traditionally, PVI for a congressional district has been calculated by comparing how that congressional district voted in a given election, to a 'baseline' of how the country as a whole voted in the last two presidential elections.
This project aims to produce PVI metrics for state legislative districts. The 'baseline' will be adapted to factor in state-wide executive office election returns, as well as presidential election returns from that state for last two presidential elections.
Texas Enacted new state legislative district boundaries after the 2020 census. Calculating the PVI in a redistricting year requires matching vote tallies from previous elections to the new geographic boundaries of legislative districts.
This project uses precint-level election returns for 2016, 2018 and 2020, and will match voting precint geographies for each year of election returns to the 2022 state legislative district they fall under.
Many thanks to the Voting Science and Elections Team (VEST) for their painstaking compilation and validation of election returns by precinct! Shapefiles for 2022 and 2012-2021 legislative districts were downloaded from Texas's Capital Data Portal
Voting and Election Science Team, 2018, "2016 Precinct-Level Election Results", https://doi.org/10.7910/DVN/NH5S2I, Harvard Dataverse, V83
Voting and Election Science Team, 2019, "2018 Precinct-Level Election Results", https://doi.org/10.7910/DVN/UBKYRU, Harvard Dataverse, V59
Voting and Election Science Team, 2020, "2020 Precinct-Level Election Results", https://doi.org/10.7910/DVN/K7760H, Harvard Dataverse, V35
Texas Legislative Council, 2022, "PLANH2316", Retrieved from https://data.capitol.texas.gov/dataset/planh2316, Texas Capital Data Portal
Texas Legislative Council, 2022, "PLANS2168", Retrieved from https://data.capitol.texas.gov/dataset/plans2168, Texas Capital Data Portal
Texas Legislative Council, 2021, "PLANH283", Retrieved from https://data.capitol.texas.gov/dataset/planplanh283, Texas Capital Data Portal
Texas Legislative Council, 2021, "PLANS148", Retrieved from https://data.capitol.texas.gov/dataset/plans148, Texas Capital Data Portal