Highway1: Highway accidents

In alr4: Data to Accompany Applied Linear Regression 4th Edition

Description

The data comes from a unpublished master's paper by Carl Hoffstedt. They relate the automobile accident rate, in accidents per million vehicle miles to several potential terms. The data include 39 sections of large Highways in the state of Minnesota in 1973. The goal of this analysis was to understand the impact of design variables, acpts, slim, Sig, and shld that are under the control of the Highway department, on accidents.

Format

This data frame contains the following columns:

adt

average daily traffic count in thousands

trks

truck volume as a percent of the total volume

lane

total number of lanes of traffic

acpt

number of access points per mile

sigs

number of signalized interchanges per mile

itg

number of freeway-type interchanges per mile

slim

speed limit in 1973

len

length of the Highway segment in miles

lwid

lane width, in feet

shld

width in feet of outer shoulder on the roadway

htype

An indicator of the type of roadway or the source of funding for the road; "mc" for major collector, "fai" for Federal interstate highways, "pa" for principal arterial highway, and "ma" for major arterial highways

rate

1973 accident rate per million vehicle miles

Source

Carl Hoffstedt

References

Weisberg, S. (2014). Applied Linear Regression, 4th edition. Hoboken NJ: Wiley.

Examples

head(Highway)

Example output

Loading required package: car
Loading required package: effects
Loading required package: carData

Attaching package: 'carData'

The following objects are masked from 'package:car':

    Guyer, UN, Vocab

lattice theme set by effectsTheme()
See ?effectsTheme for details.
  adt trks lane acpt sigs  itg slim   len lwid shld htype rate
1  69    8    8  4.6 0.00 1.20   55  4.99   12   10   fai 4.58
2  73    8    4  4.4 0.00 1.43   60 16.11   12   10   fai 2.86
3  49   10    4  4.7 0.00 1.54   60  9.75   12   10   fai 3.02
4  61   13    6  3.8 0.00 0.94   65 10.65   12   10   fai 2.29
5  28   12    4  2.2 0.00 0.65   70 20.01   12   10   fai 1.61
6  30    6    4 24.8 1.84 0.34   55  5.97   12   10    pa 6.87

alr4 documentation built on May 2, 2019, 6:40 p.m.