openintro (version 1.7.1)

cars: cars

Description

A data frame with 54 rows and 6 columns. The columns represent the variables type, price, mpgCity, driveTrain, passengers, weight for a sample of 54 cars from 1993. This data is a subset of the Cars93 data set from the MASS package.

Usage

data(cars)

Format

A data frame with 54 observations on the following 6 variables.

type

The vehicle type with levels large, midsize, and small.

price

Vehicle price (USD).

mpgCity

Vehicle mileage in city (miles per gallon).

driveTrain

Vehicle drive train with levels 4WD, front, and rear.

passengers

The vehicle passenger capacity.

weight

Vehicle weight (lbs).

Details

These cars represent a random sample for 1993 models that were in both Consumer Reports and PACE Buying Guide. Only vehicles of type 'small', 'midsize', and 'large' were include.

Further description can be found in Lock (1993). Use the URL http://www.amstat.org/publications/jse/v1n1/datasets.lock.html.

References

http://www.openintro.org/

Examples

# NOT RUN {
data(cars)

#===> vehicle price by type <===#
par(mfrow=c(1,1))
histPlot(cars$price[cars$type=='small'], probability=TRUE,
	hollow=TRUE, xlim=c(0,50))
histPlot(cars$price[cars$type=='midsize'], probability=TRUE,
	hollow=TRUE, add=TRUE, border='red', lty=3)
histPlot(cars$price[cars$type=='large'], probability=TRUE,
	hollow=TRUE, add=TRUE, border='blue', lty=4)
legend('topright', lty=2:4, col=c('black', 'red', 'blue'),
	legend=c('small', 'midsize', 'large'))

#===> vehicle price versus weight <===#
plot(cars$weight, cars$price, col=fadeColor('magenta', '88'),
	pch=20, cex=2)

#===> mileage versus weight <===#
plot(cars$weight, cars$mpgCity, type="n")
temp <- c(seq(1000, 5000, 100), rev(seq(1000, 5000, 100)), 1000)
hold <- 87.11 - 0.03508*temp + 0.000004432*temp^2 + 7*c(rep(-1, 41), rep(1, 41), 1)
polygon(temp, hold, col="#E2E2E2",
	border=fadeColor('black', '00'))
points(cars$weight, cars$mpgCity,
	col='chocolate4', pch=20, cex=2)
# }