Unpaired T Test Formula. Paired t test a paired t test is used to investigate the change in the mean of a population before and after some experimental intervention based on a paired sample i e when each subject has been measured twice. T frac bar x 1 bar x 2 sqrt frac s 1 2 n 1 frac s 2 2 n 2 where.
To test the null hypothesis that the two population means µ. So using that formula above we will see the mean difference between two independent sample with the null hypothesis is. Then select the unpaired t test from the parametric methods section of the analysis menu.
Once t test statistic value is determined you have to read in t test table the critical value of student s t distribution corresponding to the significance level alpha of your choice 5.
Mean of high protein 120 n 12 mean of low protein 101 n 7 assuming equal variances. Calculate the difference between the two sample means x. T frac m a m b sqrt frac s 2 n a frac s 2 n b where. This test is sometimes referred to as an independent samples t test or an unpaired samples t test.
