Unpaired (Two Sample) t Test | t test degree of freedom
Unpaired(TwoSample)tTest-StatsDirectOpentopicwithnavigation[1] Menulocation:Analysis_Parametric_Unpairedt. ThisfunctiongivesanunpairedtwosampleStudentt[2]testwithaconfidenceintervalforthedifferencebetweenthemeans. Theunpairedtmethodteststhenullhypothesisthatthepopulationmeansrelatedtotwoindependent,randomsamplesfromanapproximatelynormaldistributionareequal(Altman,1991;ArmitageandBerry,1994[3]). Assumingequalvariances,theteststatisticiscalculatedas:-wherexbar1andxbar2arethesamplemeans,s²isthe...
Unpaired (Two Sample) t Test - StatsDirectOpen topic with navigation[1]
Menu location: Analysis_Parametric_Unpaired t.
This function gives an unpaired two sample Student t[2] test with a confidence interval for the difference between the means.
The unpaired t method tests the null hypothesis that the population means related to two independent, random samples from an approximately normal distribution are equal (Altman, 1991; Armitage and Berry, 1994[3]).
Assuming equal variances, the test statistic is calculated as:
- where x bar 1 and x bar 2 are the sample means, s² is the pooled sample variance, n1 and n2 are the sample sizes and t is a Student t quantile with n1 + n2 - 2 degrees of freedom.
Power i...