## Educational-level data, downloaded from
##   http://www.ers.usda.gov/webdocs/DataFiles/CountyLevel_Data_Sets_Download_Data__18026//Education.xls
## on Nov 10, 2016.
ee <- read.csv("12s0233.csv",skip=5,header=FALSE,encoding="utf8", stringsAsFactors=FALSE)

## Use 'letters' to simplify lookup in CSV file.
l <- letters
e <- data.frame(state=ee[,1],
                highschool=ee[, which(l=='t')],
                bachelor=ee[, which(l=='u')],
                advanced=ee[, which(l=='v')])
## Remove whole country, and also remove some summary lines at end.
e <- e[-1,]
education <- head(e, -5)

## Voting data, downloaded by cutting and pasting a table at
##   http://www.nbcnews.com/politics/2016-election/president
## downloaded as of 1611h AST on Nov 10, 2016. (NOTE: the
## text had '%' characters in several columns, but these
## were deleted.)
votes <- read.delim("election2016votes.dat",sep="\t", header=FALSE,
                    stringsAsFactors=FALSE,
                    col.names=c("state", "electoralVotes",
                                "percentIn", "Clinton", "Trump"))
votes$ratio <- votes$Clinton / votes$Trump
votes$index <- ifelse(votes$ratio > 1, votes$ratio-1, -1/votes$ratio+1)
votes$index <- (votes$Clinton - votes$Trump) / (votes$Clinton+votes$Trump)

## Check that tables are aligned
stopifnot(length(votes$state)==sum(votes$state==education$state))


if (!interactive()) png("election2016-usa.png")
par(mar=c(3, 3, 1, 1), mgp=c(2, 0.7, 0))
## hist(education$advanced, main="", xlab="Percent with advanced degree")

## what was the outlier?
subset(education,advanced>20)
## Oh, DC...
DC <- which(education$advanced>20)
## How did they vote in DC?
votes[DC,]


division <- 10.2
H <- education$advanced > division # from visual inspection
Hdem <- votes$index[H] > 0
Hrep <- votes$index[H] < 0
Ldem <- votes$index[!H] > 0
Lrep <- votes$index[!H] < 0

plot(education$advanced, votes$index,
     ylim=c(-1, 1) * max(abs(votes$index)),
     pch=21, cex=1.4,
     bg=ifelse(votes$index>0, "blue", "red"),
     xlab="Percent of population with advanced degree",
     ylab="Voting index")
abline(h=0)

abline(v=division)

mtext(paste(sum(Hdem), "states"),
      side=3, line=-3, adj=0.7, font=2, cex=1.2, col='blue')
mtext(paste(sum(Hrep), "states"),
      side=1, line=-3, adj=0.7, font=2, cex=1.2, col='red')
mtext(paste(sum(Ldem), "states"),
      side=3, line=-3, adj=0.05, font=2, cex=1.2, col='blue')
mtext(paste(sum(Lrep), "states"),
      side=1, line=-3, adj=0.05, font=2, cex=1.2, col='red')
mtext(paste(division, "%"), side=3, line=0, at=10.5)

if (!interactive()) dev.off()