alpha : float
significance level for the confidence interval, coverage is
1-alpha
alternative : string
This specifies the alternative hypothesis for the test that
corresponds to the confidence interval.
The alternative hypothesis, H1, has to be one of the following :
‘two-sided’: H1: difference in means not equal to value (default)
‘larger’ : H1: difference in means larger than value
‘smaller’ : H1: difference in means smaller than value
usevar : string, ‘pooled’ or ‘unequal’
If pooled, then the standard deviation of the samples is assumed to be
the same. If unequal, then Welsh ttest with Satterthwait degrees
of freedom is used
|