Dewpoint Data

Description

The dewpoint data frame has 72 rows and 3 columns. Monthly data were obtained for a number of sites (in Australia) and a number of months.

Usage

dewpoint

Format

This data frame contains the following columns:

maxtemp

monthly minimum temperatures

mintemp

monthly maximum temperatures

dewpt

monthly average dewpoint for each combination of minimum and maximum temperature readings (formerly dewpoint)

Source

Dr Edward Linacre, visiting fellow in the Australian National University Department of Geography.

Examples

print("Additive Model - Example 7.5")
require(splines)
attach(dewpoint)   
ds.lm <- lm(dewpt ~ bs(maxtemp,5) + bs(mintemp,5), data=dewpoint)
ds.fit <-predict(ds.lm, type="terms", se=TRUE)
oldpar <- par(mfrow=c(1,2))
plot(maxtemp, ds.fit$fit[,1], xlab="Maximum temperature",
     ylab="Change from dewpoint mean",type="n")
lines(maxtemp,ds.fit$fit[,1])
lines(maxtemp,ds.fit$fit[,1]-2*ds.fit$se[,1],lty=2)
lines(maxtemp,ds.fit$fit[,1]+2*ds.fit$se[,1],lty=2)
plot(mintemp,ds.fit$fit[,2],xlab="Minimum temperature",
     ylab="Change from dewpoint mean",type="n")
ord<-order(mintemp)
lines(mintemp[ord],ds.fit$fit[ord,2])
lines(mintemp[ord],ds.fit$fit[ord,2]-2*ds.fit$se[ord,2],lty=2)
lines(mintemp[ord],ds.fit$fit[ord,2]+2*ds.fit$se[ord,2],lty=2)
detach(dewpoint)
par(oldpar)