R: Plot Regression Line

regLine {car}

R Documentation

Plot Regression Line

Description

Plots a regression line on a scatterplot; the line is plotted between the minimum and maximum x-values.

Usage

regLine(mod, col=palette()[2], lwd=2, lty=1,...)

Arguments

`mod`	a model, such as produced by `lm`, that responds to the `coef` function by returning a 2-element vector, whose elements are interpreted respectively as the intercept and slope of a regresison line.
`col`	color for points and lines; the default is the second entry in the current color palette (see `palette` and `par`).
`lwd`	line width; default is `2` (see `par`).
`lty`	line type; default is `1`, a solid line (see `par`).
`...`	optional arguments to be passed to the `lines` plotting function.

Details

In contrast to abline, this function plots only over the range of the observed x-values. The x-values are extracted from mod as the second column of the model matrix.

Value

NULL. This function is used for its side effect: adding a line to the plot.

Author(s)

John Fox jfox@mcmaster.ca

Examples

plot(repwt ~ weight, pch=c(1,2)[sex], data=Davis)
regLine(lm(repwt~weight, subset=sex=="M", data=Davis))
regLine(lm(repwt~weight, subset=sex=="F", data=Davis), lty=2)

[Package car version 2.0-12 Index]