R330 (version 1.0)

traffic.df: Highway accdient rates

Description

Data gathered in the course of studying the relationship between accident rates on US highways and various characteristics of the highway

Usage

data(traffic.df)

Format

A data frame with 39 observations on the following 15 variables:

obs

observation number

rate

The accident rate per million vehicle miles (response)

len

The length of the segment of highway in miles

adt

Average daily traffic count ('000)

trks

The percentage of the traffic that are trucks

slim

the speed limit in mph

lwd

the lane width in feet

shld

the shoulder width in feet

itg

number of freeway interchanges per mile

sigs

number of entrances controlled by lights per mile

acpt

number of access points per mile

lane

number of lanes in each direction

fai

dummy variable, equal to 1 if an interstate highway, zero otherwise

pa

equal to 1 if a principal highway, 0 otherwise

ma

equal to 1 if a major highway, 0 otherwise

Source

Carl Hoffstedt. This differs from the dataset highway in the alr3 package only by transformation of some of the columns.

References

Fox, J. and Weisberg, S. (2011) An R Companion to Applied Regression, Second Edition, Sage.

Weisberg, S. (2005) Applied Linear Regression, Third Edition. Wiley, Section 7.2.

Examples

data(traffic.df)
traffic.lm<-lm(rate~.,data=traffic.df)
summary(traffic.lm)