Perform a F-test for equal variances.
If the second argument y is a vector, a paired-t test of the
hypothesis mean (x) = mean (y)
is performed.
The argument "alpha"
can be used to specify the significance level
of the test (the default value is 0.05). The string
argument "tail"
, can be used to select the desired alternative
hypotheses. If "alt"
is "both"
(default) the null is
tested against the two-sided alternative mean (x) != m
.
If "alt"
is "right"
the one-sided
alternative mean (x) > m
is considered.
Similarly for "left"
, the one-sided alternative mean
(x) < m
is considered. When "vartype"
is "equal"
the variances are assumed to be equal (this is the default). When
"vartype"
is "unequal"
the variances are not assumed equal.
When argument x is a matrix the "dim"
argument can be
used to selection the dimension over which to perform the test.
(The default is the first non-singleton dimension.)
If h is 0 the null hypothesis is accepted, if it is 1 the null hypothesis is rejected. The p-value of the test is returned in pval. A 100(1-alpha)% confidence interval is returned in ci. stats is a structure containing the value of the test statistic (tstat), the degrees of freedom (df) and the sample standard deviation (sd).
Package: statistics