| plot.profile.nls {nls} | R Documentation |
Plot a profile.nls Object
Usage
plot.profile.nls(x, levels, conf, nseg, absVal, ...)
Arguments
x |
an object of class |
levels |
levels, on the scale of the absolute value of a t
statistic, at which to interpolate intervals. Usually |
conf |
a numeric vector of confidence levels for profile-based
confidence intervals on the parameters. Defaults to |
Displays a series of plots of the profile t function and
interpolated confidence intervals for the parameters in a nonlinear
regression model that has been fit with nls and profiled with
profile.nls.
Bates, D.M. and Watts, D.G. (1988), Nonlinear Regression Analysis
and Its Applications, Wiley (chapter 6)
Douglas M. Bates and Saikat DebRoy
nls, profile, profile.nls
library( nls )
data( BOD )
# obtain the fitted object
fm1 <- nls(demand ~ SSasympOrig( Time, A, lrc ), data = BOD)
# get the profile for the fitted model
pr1 <- profile( fm1 )
opar <- par(mfrow = c(2,2), oma = c(1.1, 0, 1.1, 0), las = 1)
plot(pr1, conf = c(95, 90, 80, 50)/100)
plot(pr1, conf = c(95, 90, 80, 50)/100, absVal = FALSE)
mtext("Confidence intervals based on the profile sum of squares",
side = 3, outer = TRUE)
mtext("BOD data - confidence levels of 50%, 80%, 90% and 95%",
side = 1, outer = TRUE)
par(opar)
nonlinear
regression
models