Question

If other factors are held constant, how does sample variance influence the likelihood of rejecting the null hypothesis and the measure of effect size (i.e. Cohen’s d)?

Answer 1

Answer :

As per the given question,

Here we realize that change is contrarily corresponding to the test statisic so on expanding the sample variance will decreases test statisic and will make it less Significant additionally impact size of test is conversely relative to variance. So on expanding variance impact size decreases.

i.e Larger sample variances decreases the likelihood of the Rejecting the null Hypothesis H0 and effect size such as Cohen's D.

test statistice t =

where = standard deviation.

= sample size.

and Cohen's D =