openintro (version 1.7.1)

prRace08: Election results for the 2008 U.S. Presidential race

Description

Election results for the 2008 U.S. Presidential race

Usage

data(prRace08)

Format

A data frame with 51 observations on the following 7 variables.

state

State name abbreviation

stateFull

Full state name

nObama

Number of votes for Barack Obama

pObama

Proportion of votes for Barack Obama

nMcCain

Number of votes for John McCain

pMcCain

Proportion of votes for John McCain

elVotes

Number of electoral votes for a state

Details

In Nebraska, 4 electoral votes went to McCain and 1 to Obama. Otherwise the electoral votes were a winner-take-all.

Examples

# NOT RUN {
#===> Obtain 2010 US House Election Data <===#
data(houseRace10)
hr <- table(houseRace10[,c("abbr", "party1")])
nr <- apply(hr, 1, sum)

#===> Obtain 2008 President Election Data <===#
data(prRace08)
pr   <- prRace08[prRace08$state != "DC",c("state", "pObama")]
hr   <- hr[as.character(pr$state),]
(fit <- glm(hr ~ pr$pObama, family=binomial))

#===> Visualizing Binomial outcomes <===#
x  <- pr$pObama[pr$state != "DC"]
nr <- apply(hr, 1, sum)
plot(x, hr[,"Democrat"]/nr, pch=19, cex=sqrt(nr), col="#22558844",
    xlim=c(20, 80), ylim=c(0, 1), xlab="Percent vote for Obama in 2008",
    ylab="Probability of Democrat winning House seat")

#===> Logistic Regression <===#
x1 <- pr$pObama[match(houseRace10$abbr, pr$state)]
y1 <- (houseRace10$party1 == "Democrat")+0
g  <- glm(y1 ~ x1, family=binomial)
X  <- seq(0, 100, 0.1)
lo <- -5.6079 + 0.1009*X
p  <- exp(lo)/(1+exp(lo))
lines(X, p)
abline(h=0:1, lty=2, col="#888888")
# }