Bartlett Test for Homogeneity of Variances
Usage
bartlett.test(x, g)
Arguments
x
|
a numeric vector of data values, or a list of numeric data
vectors.
|
g
|
a vector or factor object giving the group for the
corresponding elements of x .
Ignored if x is a list.
|
Description
bartlett.test
performs Bartlett's test of the null that the
variances in each of the groups (samples) are the same.Details
If x
is a list, its elements are taken as the samples to be
compared for homogeneity of variances, and hence have to be numeric
data vectors. In this case, g
is ignored, and one can simply
use bartlett.test(x)
to perform the test. If the samples are
not yet contained in a list, use bartlett.test(list(x, ...))
.
Otherwise, x
must be a numeric data vector, and g
must
be a vector or factor object of the same length as x
giving
the group for the corresponding elements of x
.
Value
A list of class "htest"
containing the following components:
statistic
|
Bartlett's K-square test statistic.
|
parameter
|
the degrees of freedom of the approximate
chi-square distribution of the test statistic.
|
p.value
|
the p-value of the test.
|
method
|
the string
"Bartlett test for homogeneity of variances" .
|
data.name
|
a character string giving the names of the data.
|