ABSTRACT
Hypothesis evaluated with test Do two dependent samples represent two populations with different mean values?
In conducting the t test for two dependent samples, the means of the two experimental conditions (represented by the notations X, and X,) are employed to estimate the values of the means of the populations ( pl and k) the conditions represent. If the result of the t test for two dependent samples is significant, it indicates the researcher can conclude there is a high likelihood that the two experimental conditions represent populations with different mean values. It should be noted that the t test for two dependent samples is the appropriate test to employ for contrasting the means of two dependent samples when the values of the underlying population variances are unknown. In instances where the latter two values are known, the appropriate test to employ is the z test for two dependent samples (Test 17e), which is described in Section W.
