| yuen.t.test | R Documentation |
Yuen's test for one, two or paired samples.
yuen.t.test(x, ...)
## Default S3 method:
yuen.t.test(x, y = NULL, tr = 0.2, alternative = c("two.sided", "less", "greater"),
mu = 0, paired = FALSE, conf.level = 0.95, ...)
## S3 method for class 'formula'
yuen.t.test(formula, data, subset, na.action, ...)
## S3 method for class 'paired'
yuen.t.test(x, ...)
x |
first sample or object of class paired. |
y |
second sample. |
tr |
percentage of trimming. |
alternative |
alternative hypothesis. |
mu |
a number indicating the true value of the trimmed mean (or difference in trimmed means if you are performing a two sample test). |
paired |
a logical indicating whether you want a paired yuen's test. |
conf.level |
confidence level. |
formula |
a formula of the form y ~ f where y is a numeric variable giving the data values and f a factor with TWO levels giving the corresponding groups. |
data |
an optional matrix or data frame (or similar: see model.frame) containing the variables in the formula formula. By default the variables are taken from environment(formula). |
subset |
an optional vector specifying a subset of observations to be used. |
na.action |
a function which indicates what should happen when the data contain NAs. Defaults to getOption("na.action"). |
... |
further arguments to be passed to or from methods. |
A list with class "htest" containing the following components:
statistic |
the value of the t-statistic. |
parameter |
the degrees of freedom for the t-statistic. |
p.value |
the p-value for the test. |
conf.int |
a confidence interval for the trimmed mean appropriate to the specified alternative hypothesis. |
estimate |
the estimated trimmed mean or difference in trimmed means depending on whether it was a one-sample test or a two-sample test. |
null.value |
the specified hypothesized value of the trimmed mean or trimmed mean difference depending on whether it was a one-sample test or a two-sample test. |
alternative |
a character string describing the alternative hypothesis. |
method |
a character string indicating what type of test was performed. |
data.name |
a character string giving the name(s) of the data. |
Stephane CHAMPELY, but some part are mere copy of the code of Wilcox (WRS)
Wilcox, R.R. (2005). Introduction to robust estimation and hypothesis testing. Academic Press.
Yuen, K.K. (1974) The two-sample trimmed t for unequal population variances. Biometrika, 61, 165-170.
t.test
z<-rnorm(20) x<-rnorm(20)+z y<-rnorm(20)+z+1 # two-sample test yuen.t.test(x,y) # one-sample test yuen.t.test(y,mu=1,tr=0.25) # paired-sample tests yuen.t.test(x,y,paired=TRUE) p<-paired(x,y) yuen.t.test(p)