a <- read.table("http://www.stat.ucla.edu/~nchristo/statistics13/nc_sids_data.txt", header=TRUE)

b <- read.table("http://www.stat.ucla.edu/~nchristo/statistics13/nc_seats.txt", header=TRUE)

names(a)
names(b)

#Get number of SIDS per 1000 births:
Q1 <- 1000*(a$sids1+1)/a$births1     #1974-1978 data
Q2 <- 1000*(a$sids2+1)/a$births2     #1979-1984 data


hist(Q1)
hist(log(Q1))

hist(Q2)
hist(log(Q2))

boxplot(Q1)
boxplot(log(Q1))

boxplot(Q2)
boxplot(log(Q2))

library(maps)
map("county", "north carolina")
points(b$lon, b$lat, cex=Q1/mean(Q1), pch=19)


map("county", "north carolina")
points(b$lon, b$lat, cex=Q2/mean(Q2), pch=19)