rockchalk (version 1.6.3)

addLines: Superimpose regression lines on a plotted plane

Description

The examples will demonstrate the intended usage.

Usage

addLines(to = NULL, from = NULL, col = "red", lwd = 2,
    lty = 1)

Arguments

to

a 3d plot object produced by plotPlane

from

output from a plotSlopes or plotCurves function (class="rockchalk")

col

color of plotted lines (default: "red")

lwd

line width of added lines (default: 2)

lty

line type of added lines (default: 1)

Value

• NULL, nothing, nicht, nada.

Details

From an educational stand point, the objective is to assist with the student's conceptualization of the two and three dimensional regression relationships.

Examples

library(rockchalk)


set.seed(12345)
x1 <- rnorm(100)
x2 <- rnorm(100)
x3 <- rnorm(100)
x4 <- rnorm(100)
xcat1 <- gl(2,50, labels=c("M","F"))
xcat2 <- cut(rnorm(100), breaks=c(-Inf, 0, 0.4, 0.9, 1, Inf), labels=c("R", "M", "D", "P", "G"))
y <- rnorm(100)
y2 <- 0.03 + 0.1*x1 + 0.1*x2 + 0.25*x1*x2 + 0.4*x3 -0.1*x4 + 1*rnorm(100)
dat <- data.frame(x1,x2,x3,x4,xcat1, xcat2, y, y2)
rm(x1, x2, x3, x4, y, y2, xcat1, xcat2)

## linear ordinary regression
m1 <- lm(y ~ x1 + x2 + x3 + x4, data = dat)

##ordinary regression.
dat$y <- with(dat, 0.03 + 0.1*x1 + 0.1*x2 + 0.4*x3 -0.1*x4 + 2*rnorm(100))
m1 <- lm(y ~ x1 + x2 +x3 + x4, data=dat)
## These will be parallel lines emf

plotSlopes(m1, plotx="x1", modx="x2", modxVals="std.dev.", main="A plotSlopes result with \"std.dev.\"values of modx")


m1ps <- plotSlopes(m1, plotx="x1", modx="x2", modxVals=c(-0.5,0,0.5))
m1pp <- plotPlane(m1, plotx1="x1", plotx2="x2", ticktype="detailed")
addLines(from = m1ps, to = m1pp, lty = 2, lwd = 5, col = "green")