| whiteside(MASS) | R Documentation |
Mr Derek Whiteside of the UK Building Research Station recorded the weekly gas consumption and average external temperature at his own house in south-east England for 26 weeks before, and 30 weeks after cavity-wall insulation was installed. The object of the exercise was to assess the effect of the insulation on gas consumption.
Insul |
A factor, before or after insulation. |
Temp |
Purportedly the average outside temperature in degrees Celsius. (These values is far too low for any 56-week period in the 1960s in South-East England. It might be the weekly average of daily minima.) |
Gas |
The weekly gas consumption in 1000s of cubic feet. |
The whiteside data frame has 56 rows and 3 columns.:
A data set collected in the 1960s by Mr Derek Whiteside of the UK~Building Research Station. Reported by
Hand, D. J., Daly, F., McConway, K., Lunn, D. and Ostrowski, E. eds (1993) A Handbook of Small Data Sets. Chapman & Hall, p. 69.
data(whiteside)
coplot(Gas ~ Temp | Insul, whiteside, panel =
function(x, y, ...) {
points(x, y, ...)
abline(lm(y ~ x))
}, xlab = "Average external temperature (deg. C)",
ylab = "Gas consumption (1000 cubic feet)")
gasB <- lm(Gas ~ Temp, whiteside, subset=Insul=="Before")
gasA <- update(gasB, subset=Insul=="After")
summary(gasB)
summary(gasA)
gasBA <- lm(Gas ~ Insul/Temp - 1, whiteside)
summary(gasBA)
gasQ <- lm(Gas ~ Insul/(Temp + I(Temp^2)) - 1, whiteside)
summary(gasQ)$coef
gasPR <- lm(Gas ~ Insul + Temp, whiteside)
anova(gasPR, gasBA)
options(contrasts = c("contr.treatment", "contr.poly"))
gasBA1 <- lm(Gas ~ Insul*Temp, whiteside)
summary(gasBA1)$coef