Find and optionally plot the marginal (profile) likelihood for alpha
for a transformation model of the form log(y + alpha) ~ x1 + x2 + ....
Usage
logtrans(object, ...)
## Default S3 method:
logtrans(object, ..., alpha = seq(0.5, 6, by = 0.25) - min(y),
plotit = TRUE, interp =, xlab = "alpha",
ylab = "log Likelihood")
## S3 method for class 'formula'
logtrans(object, data, ...)
## S3 method for class 'lm'
logtrans(object, ...)
Arguments
object
Fitted linear model object, or formula defining the untransformed
model that is y ~ x1 + x2 + .... The function is generic.
...
If object is a formula, this argument may specify a data frame
as for lm.
alpha
Set of values for the transformation parameter, alpha.
plotit
Should plotting be done?
interp
Should the marginal log-likelihood be interpolated with a spline
approximation? (Default is TRUE if plotting is to be done and
the number of real points is less than 100.)
xlab
as for plot.
ylab
as for plot.
data
optional data argument for lm fit.
Value
List with components x (for alpha) and y (for the marginal
log-likelihood values).
Side Effects
A plot of the marginal log-likelihood is produced, if requested,
together with an approximate mle and 95% confidence interval.
References
Venables, W. N. and Ripley, B. D. (2002)
Modern Applied Statistics with S. Fourth edition. Springer.
R version 3.3.1 (2016-06-21) -- "Bug in Your Hair"
Copyright (C) 2016 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)
R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type 'license()' or 'licence()' for distribution details.
R is a collaborative project with many contributors.
Type 'contributors()' for more information and
'citation()' on how to cite R or R packages in publications.
Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.
> library(MASS)
> png(filename="/home/ddbj/snapshot/RGM3/R_CC/result/MASS/logtrans.Rd_%03d_medium.png", width=480, height=480)
> ### Name: logtrans
> ### Title: Estimate log Transformation Parameter
> ### Aliases: logtrans logtrans.formula logtrans.lm logtrans.default
> ### Keywords: regression models hplot
>
> ### ** Examples
>
> logtrans(Days ~ Age*Sex*Eth*Lrn, data = quine,
+ alpha = seq(0.75, 6.5, len=20))
>
>
>
>
>
> dev.off()
null device
1
>