t test

I’ll play: 
The answer is “When do I use a t-test”? 
I’ll take hypothesis testing for 200, Alex!

Hi RobertMay I pick a nit here? You can of course use ANOVA with just two means as you are no doubt aware. It’s quite interesting to do an example by both methods with people learning the ropes of hypothesis testing: -Row A B
1 20.4 20.2
2 24.2 16.9
3 15.4 18.5
4 21.4 17.3
5 20.2 20.5
6 18.5
7 21.5T-Test of difference = 0 (vs not =): T-Value = 1.12 P-Value = 0.289 DF = 10
Both use Pooled StDev = 2.3627
One-Way ANOVA
Source DF SS MS F P
Factor 1 6.99 6.99 1.25 0.289
Error 10 55.82 5.58
Total 11 62.82The P-values are the same for both the t-test and the ANOVA and in fact the F statistic is the square of the t-statistic. Thus the t-test is equivalent to the ANOVA F-test in this case.Best Wishes
Bower Chiel

RobertApologies for my garbled post – what looked fine on screen appeared as a dog’s breakfast on-line!Sample A 20.4 24.2 15.4 21.4 20.2 18.5 21.5
Sample B 20.2 16.9 18.5 17.3 20.5A t-test of mean for Population A equals mean for Population B, versus the alternative that they differ, gives t = 1.12 and P-value of 0.289 (equal population variances assumed).ANOVA for the same hypotheses gives F = 1.25 and P-value of 0.289.The P-values are identical and in fact the F value is the square of the t value – the two tests are exactly equivalent.It’s also interesting to consider the ANOVA alternative to the paired t-test.Best WishesBower Chiel