allbacks: Measurements on a Selection of Books

Description

The allbacks data frame gives measurements on the volume and weight of 15 books, some of which are softback (pb) and some of which are hardback (hb). Area of the hardback covers is also included.

Usage

allbacks

Arguments

Format

This data frame contains the following columns:

volume: book volumes in cubic centimeters
area: hard board cover areas in square centimeters
weight: book weights in grams
cover: a factor with levels hb hardback, pb paperback

Examples

Run this code

# NOT RUN {
print("Multiple Regression - Example 6.1")
attach(allbacks)
volume.split <- split(volume, cover)
weight.split <- split(weight, cover)
plot(weight.split$hb ~ volume.split$hb, pch=16, xlim=range(volume), ylim=range(weight),
     ylab="Weight (g)", xlab="Volume (cc)")
points(weight.split$pb ~ volume.split$pb, pch=16, col=2)
pause()

allbacks.lm <- lm(weight ~ volume+area)
summary(allbacks.lm)
detach(allbacks)
pause()

anova(allbacks.lm)
pause()

model.matrix(allbacks.lm)
pause()

print("Example 6.1.1")
allbacks.lm0 <- lm(weight ~ -1+volume+area, data=allbacks)
summary(allbacks.lm0)
pause()

print("Example 6.1.2")
oldpar <- par(mfrow=c(2,2))
plot(allbacks.lm0)
par(oldpar)
allbacks.lm13 <- lm(weight ~ -1+volume+area, data=allbacks[-13,])
summary(allbacks.lm13)
pause()

print("Example 6.1.3")
round(coef(allbacks.lm0),2)  # Baseline for changes
round(lm.influence(allbacks.lm0)$coef,2)
# }

Run the code above in your browser using DataCamp Workspace