diff --git a/Makefile b/Makefile
index 7c2a9e1..9e22407 100644
--- a/Makefile
+++ b/Makefile
@@ -14,3 +14,5 @@ figure-cv.pdf: figure-cv.R
 	R --vanilla < $<
 figure-cv-BIC.pdf: figure-cv-BIC.R
 	R --vanilla < $<
+figure-sequence-cv.pdf: figure-sequence-cv.R
+	R --vanilla < $<
diff --git a/README.org b/README.org
index 7c0d28c..1bc9c91 100644
--- a/README.org
+++ b/README.org
@@ -8,6 +8,9 @@ Figures for Labeled Optimal PARTitioning paper
 - Cross-validation label error figures. [[file:figure-cv.R][R script]], [[file:figure-cv.pdf][OPART pdf (Fig 3
   right)]], [[file:figure-cv-SegAnnot.pdf][SegAnnot pdf (Fig 4 right)]], [[file:figure-cv-roc.pdf][Fig 5 ROC curves]].
 - Comparison with BIC figures. [[file:figure-cv-BIC.R][R script]], [[file:figure-cv-BIC-roc.pdf][ROC curves]], [[file:figure-cv-BIC.pdf][Error rates]].
+- Sequential cross-validation (fold 1 = first half of labels, fold 2 =
+  second half labels) figures. [[file:figure-sequence-cv.R][R script]], [[file:figure-sequence-cv-OPART.pdf][Best case OPART differences]],
+  [[file:figure-sequence-cv-SegAnnot.pdf][Best case SegAnnot differences]], [[file:figure-sequence-cv-roc.pdf][ROC curves]], [[file:figure-sequence-cv.pdf][Test error rates]].
 
 Reproducibility: use "make" with one of the recipes defined in
 [[file:Makefile]].
diff --git a/figure-sequence-cv-OPART.pdf b/figure-sequence-cv-OPART.pdf
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diff --git a/figure-sequence-cv-SegAnnot.pdf b/figure-sequence-cv-SegAnnot.pdf
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index 0000000..afa74ec
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diff --git a/figure-sequence-cv-roc.pdf b/figure-sequence-cv-roc.pdf
new file mode 100644
index 0000000..3e9bbef
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diff --git a/figure-sequence-cv.R b/figure-sequence-cv.R
new file mode 100644
index 0000000..6e70fb8
--- /dev/null
+++ b/figure-sequence-cv.R
@@ -0,0 +1,343 @@
+source("packages.R")
+
+err.dt <- data.table(
+  csv=Sys.glob("figure-sequence-cv-data/*.csv")
+)[, data.table::fread(
+  csv,
+  colClasses=list(character=5)
+), by=csv]
+err.dt[model.name=="LOPART" & set=="train", table(errors)]
+err.dt[model.name=="LOPART" & set=="train" & 0<errors, .(
+  csv, test.fold, set, penalty, fp, fn)]
+
+fn.dt <- err.dt[set=="test", .(
+  fn=possible.fn[1]
+), by=.(sequenceID, test.fold)]
+
+SegAnnot.compare <- err.dt[
+  set=="test" & model.name=="LOPART",
+  .SD[which.min(errors)],
+  by=.(sequenceID, test.fold)]
+## segannot always has FN = possible.fn and FP=0, so how often are we
+## better on one or both axes?
+SegAnnot.compare[, fewer.FN := possible.fn-fn]
+SegAnnot.compare[, table(fp, fewer.FN)]
+SegAnnot.compare[, table(fewer.FN>fp)]
+
+SegAnnot.compare.counts <- SegAnnot.compare[, .(
+  test.sets=.N
+), by=.(fewer.FN, fp)]
+SegAnnot.compare.counts[, .(
+  test.sets=sum(test.sets)
+), by=.(same = fp==fewer.FN)]
+my.title <- ggtitle("Best penalty")
+scale.fill <- scale_fill_gradient(
+  "log10(seqs)",
+  low="white",
+  high="violet")
+gg <- ggplot()+
+  ##ggtitle("LOPART is more accurate than SegAnnot")+
+  my.title+
+  geom_abline(aes(
+    slope=slope, intercept=intercept, color=test.errors),
+    data=data.table(slope=1, intercept=0, test.errors="equal"))+
+  scale_color_manual(values=c(equal="grey"), guide=FALSE)+
+  geom_tile(aes(
+    fewer.FN, fp, fill=log10(test.sets)),
+    alpha=0.8,
+    data=SegAnnot.compare.counts)+
+  geom_text(aes(
+    fewer.FN, fp, label=test.sets),
+    data=SegAnnot.compare.counts)+
+  scale.fill+
+  coord_equal()+
+  theme_bw()+
+  scale_x_continuous(
+    "Number of LOPART true positive labels
+(SegAnnot always has true positives=0)")+
+  scale_y_continuous(
+    "Number of LOPART
+false positive labels
+(SegAnnot always has
+false positives=0)")
+pdf("figure-sequence-cv-SegAnnot.pdf", width=5, height=2.3)
+print(gg)
+dev.off()
+
+total.dt <- dcast(
+  data.table(data.frame(err.dt)),
+  sequenceID + test.fold + model.name + penalty ~ set,
+  value.var="errors")
+total.dt[, train.test := test+train]
+total.min <- total.dt[, .SD[
+  which.min(train.test)], by=.(sequenceID, test.fold, model.name)]
+total.min.wide <- dcast(
+  total.min,
+  sequenceID + test.fold ~ model.name,
+  value.var=c("test", "train", "train.test"))
+total.min.wide[, diff := train.test_OPART-train.test_LOPART]
+total.min.wide[, .(
+  prob.folds=.N
+), keyby=.(diff)]
+total.min.wide[diff<0]
+total.min.wide[, train.test.diff := train.test_OPART - train.test_LOPART]
+mytab <- function(dt, col.name){
+  errors <- dt[, .(
+    count=.N,
+    percent=100*.N/nrow(dt)
+  ), by=col.name]
+  is.zero <- errors[[col.name]] == 0
+  nonzero <- errors[!is.zero]
+  sum.wide <- data.table(
+    sum.count=sum(errors$count),
+    zero.count=errors$count[is.zero],
+    nonzero.count=sum(nonzero$count),
+    nonzero.min=min(nonzero[[col.name]]),
+    nonzero.max=max(nonzero[[col.name]]))
+  sum.tall <- melt(sum.wide, measure.vars=names(sum.wide))
+  sum.tall[grepl("count", variable), percent := 100*value/nrow(dt) ]
+  list(
+    errors=errors,
+    summary=sum.tall)
+}
+mytab(total.min.wide, "train_OPART")
+
+total.min.wide[, test.diff := test_OPART-test_LOPART]
+mytab(total.min.wide, "test.diff")
+
+train.test.counts <- total.min.wide[, .(
+  splits=.N
+), by=.(train_OPART, test.diff)]
+gg <- ggplot()+
+  ##ggtitle("LOPART is more accurate\nthan OPART")+
+  my.title+
+  geom_hline(yintercept=0, color="grey")+
+  geom_vline(xintercept=0, color="grey")+
+  geom_tile(aes(
+    train_OPART, test.diff, fill=log10(splits)),
+    alpha=0.8,
+    data=train.test.counts)+
+  geom_text(aes(
+    train_OPART, test.diff, label=splits),
+    data=train.test.counts)+
+  scale.fill+
+  coord_equal()+
+  theme_bw()+
+  scale_x_continuous(
+    "OPART train label errors
+(LOPART is always=0)")+
+  scale_y_continuous(
+    "Test label error difference
+(OPART-LOPART)")
+pdf("figure-sequence-cv-OPART.pdf", width=3, height=2.3)
+print(gg)
+dev.off()
+
+err.dt[, log.penalty := log(penalty)]
+err.dt[, min.log.lambda := log.penalty + c(
+  -Inf, -diff(log.penalty)/2
+), by=.(
+  model.name, test.fold, set, sequenceID)]
+err.dt[, max.log.lambda := c(
+  min.log.lambda[-1], Inf
+), by=.(
+  model.name, test.fold, set, sequenceID)]
+err.test <- err.dt[set=="test"]
+
+err.train <- err.dt[set=="train" & model.name=="OPART"]
+
+feature.dt <- data.table::fread(
+  "data-for-LOPART-signals.csv.gz"
+)[, .(
+  log.log.data=log(log(.N))
+), by=sequenceID]
+feature.mat <- feature.dt[, matrix(
+  log.log.data,
+  ncol=1,
+  dimnames=list(sequenceID=sequenceID, feature="log.log.data"))]
+
+pred.dt <- err.train[, {
+  best.penalty <- .SD[, .(
+    train.errors=sum(errors)
+  ), by=penalty][which.min(train.errors)]
+  target.dt <- penaltyLearning::targetIntervals(.SD, "sequenceID")
+  target.mat <- target.dt[
+    rownames(feature.mat),
+    cbind(min.log.lambda, max.log.lambda),
+    on="sequenceID"]
+  keep <- -Inf < target.mat[, 1] | target.mat[,2] < Inf
+  fit <- penaltyLearning::IntervalRegressionUnregularized(
+    feature.mat[keep, , drop=FALSE], target.mat[keep, ])
+  print(fit)
+  rbind(
+    data.table(
+      sequenceID=rownames(feature.mat),
+      Penalty="constant",
+      Parameters=1,
+      pred.log.lambda=log(best.penalty$penalty)),
+    data.table(
+      sequenceID=rownames(feature.mat),
+      Penalty="BIC",
+      Parameters=0,
+      pred.log.lambda=as.numeric(feature.mat)),
+    data.table(
+      sequenceID=rownames(feature.mat),
+      Penalty="linear",
+      Parameters=2,
+      pred.log.lambda=as.numeric(fit$predict(feature.mat))))
+}, by=test.fold]
+
+auc.dt <- err.test[, {
+  select.dt <- data.table(test.fold)
+  pred.fold <- pred.dt[select.dt, on="test.fold"]
+  model.dt <- .SD[order(sequenceID, min.log.lambda)]
+  pred.fold[, {
+    roc.list <- penaltyLearning::ROChange(
+      model.dt,
+      .SD[select.dt, on="test.fold"],
+      problem.vars="sequenceID")
+    with(roc.list, data.table(
+      roc=list(roc), auc,
+      thresholds[threshold=="predicted"]))
+  }, by=.(Penalty, Parameters)]
+}, by=.(test.fold, model.name)]
+
+roc.dt <- auc.dt[, data.table(
+  roc[[1]]
+), by=.(test.fold, model.name, Penalty, Parameters)]
+possible.dt <- unique(auc.dt[, .(
+  test.fold, possible.fp, possible.fn)])
+pred.point.dt <- rbind(
+  auc.dt[model.name=="LOPART", data.table(
+    FPR=0, TPR=0, fp=0, tp=0, auc=NA, labels,
+    model.name="SegAnnot", test.fold, Penalty, Parameters
+  )],
+  auc.dt[, .(
+    FPR, TPR, fp, tp, auc, labels,
+    model.name, test.fold, Penalty, Parameters
+  )]
+)[possible.dt, on=.(test.fold)]
+algo.colors <- c(
+  OPART="#0077CC",
+  LOPART="black",
+  SegAnnot="#22CC22")
+gg <- ggplot()+
+  theme_bw()+
+  scale_color_manual(values=algo.colors)+
+  scale_size_manual(values=c(
+    LOPART=1.5,
+    OPART=1))+
+  directlabels::geom_dl(aes(
+    FPR, TPR,
+    color=model.name,
+    label=paste0(model.name, ifelse(is.na(auc), "", sprintf(
+      " AUC=%.3f", auc
+    )))),
+    method=list(
+      cex=0.8,
+      directlabels::polygon.method(
+        "right",
+        offset.cm=0.5,
+        padding.cm=0.05)),
+    data=pred.point.dt)+
+  geom_path(aes(
+    FPR, TPR,
+    color=model.name,
+    size=model.name,
+    group=paste(model.name, test.fold)),
+    data=roc.dt)+
+  geom_point(aes(
+    FPR, TPR,
+    color=model.name),
+    size=3,
+    shape=21,
+    fill="white",
+    data=pred.point.dt)+
+  theme(
+    panel.spacing=grid::unit(0, "lines"),
+    legend.position="none"
+  )+
+  facet_grid(test.fold ~ Penalty + Parameters, labeller=label_both)+
+  coord_equal()+
+  scale_x_continuous(
+    "False Positive Rate (test set labels)",
+    breaks=c(0, 0.5, 1),
+    labels=c("0", "0.5", "1"))+
+  scale_y_continuous(
+    "True Positive Rate (test set labels)",
+    breaks=c(0, 0.5, 1),
+    labels=c("0", "0.5", "1"))
+##print(gg)
+expansion <- 2.5
+pdf("figure-sequence-cv-roc.pdf", width=3*expansion, height=2*expansion)
+print(gg)
+dev.off()
+
+auc.wide <- dcast(
+  auc.dt,
+  test.fold + Parameters + Penalty ~ model.name,
+  value.var = "auc")
+auc.wide[, diff := OPART-LOPART]
+auc.wide
+
+pred.point.dt[, fn := possible.fn-tp ]
+pred.point.dt[, errors := fn + fp ]
+pred.point.dt[, percent.error := 100*errors/labels]
+pred.point.dt[, Penalty.Params := paste0(Penalty, ".", Parameters)]
+gg <- ggplot()+
+  theme_bw()+
+  theme(panel.spacing=grid::unit(0, "lines"))+
+  geom_point(aes(
+    percent.error, Penalty.Params, color=model.name),
+    data=pred.point.dt)+
+  facet_grid(. ~ test.fold, labeller=label_both)+
+  scale_color_manual(values=algo.colors)
+
+pred.point.dt[, percent.accuracy := 100-percent.error]
+pred.point.vars <- melt(
+  pred.point.dt,
+  measure.vars=c("percent.accuracy", "auc"))
+ggplot()+
+  theme_bw()+
+  theme(panel.spacing=grid::unit(0, "lines"))+
+  geom_point(aes(
+    value, Penalty.Params, color=model.name),
+    data=pred.point.vars)+
+  facet_grid(test.fold ~ variable, labeller=label_both, scales="free")+
+  scale_color_manual(values=algo.colors)
+
+ggplot()+
+  theme_bw()+
+  theme(panel.spacing=grid::unit(0, "lines"))+
+  geom_point(aes(
+    value, Penalty.Params, color=model.name),
+    data=pred.point.vars)+
+  facet_grid(. ~ variable + test.fold, labeller=label_both, scales="free")+
+  scale_color_manual(values=algo.colors)
+
+pred.point.wide <- dcast(
+  pred.point.dt,
+  test.fold + Penalty.Params ~ model.name,
+  value.var="percent.error")
+pred.point.tall <- melt(
+  pred.point.wide,
+  measure.vars=c("OPART", "SegAnnot"),
+  variable.name="competitor",
+  value.name="percent.error")
+
+ggplot()+
+  theme_bw()+
+  theme(panel.spacing=grid::unit(0, "lines"))+
+  facet_grid(. ~ competitor)+
+  geom_abline(aes(
+    slope=slope, intercept=intercept),
+    color="grey",
+    data=data.table(slope=1, intercept=0))+
+  geom_point(aes(
+    LOPART, percent.error, color=Penalty.Params),
+    data=pred.point.tall)+
+  coord_equal()
+
+pdf("figure-sequence-cv.pdf", width=4, height=2)
+print(gg)
+dev.off()
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