Highway1 {car} | R Documentation

## Highway Accidents

### 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The data comes from a unpublished master's paper by Carl Hoffstedt.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.

### Usage

    Highway1

### Format

This data frame contains the following columns:

rate

  1973 accident rate per million vehicle miles

len

  length of the `Highway1` segment in miles

adt

  average daily traffic count in thousands

trks

  truck volume as a percent of the total volume

sigs1

  (number of signalized interchanges per mile times len + 1)/len, the number of signals per mile of roadway, adjusted to have no zero values.

slim

  speed limit in 1973

shld

  width in feet of outer shoulder on the roadway

lane

  total number of lanes of traffic

acpt

  number of access points per mile

itg

  number of freeway-type interchanges per mile

lwid

  lane width, in feet

htype

  An indicator of the type of roadway or the source of funding for the road, either MC, FAI, PA, or MA

### Source

Carl Hoffstedt. This differs from the dataset `Highway` in the `alr4` package only by addition of transformation of some of the columns.

### References

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

Weisberg, S. (2014) Applied Linear Regression, Fourth Edition, Wiley, Section 7.2.

[Package car version 2.1-6 Index]