quadline {MPV}

Quadratic Overlay

Description

Overlays a quadratic curve to a fitted quadratic model.

Usage

quadline(lm.obj, ...)

Arguments

lm.obj

A lm object (a quadratic fit)

...

Other arguments to the lines function; e.g. col

Value

The function superimposes a quadratic curve onto an existing scatterplot.

Author(s)

W.J. Braun

See Also

lm

Examples

data(p4.18)
attach(p4.18)
y.lm <- lm(y ~ x1 + I(x1^2))
plot(x1, y)
quadline(y.lm)
detach(p4.18)