What statistical test do I use to find the mean of differences?

Question

I ve been looking around the internet all day for a statistical test that measures this, but all I keep finding are results for finding the difference of means. If I am to find the mean of the differences between two groups, should I simply find their individual differences and then look for their mean? Or is there a different method for this?

Answer 1

The mean of the differences is normally associated with paired T test. For example, you have two sets of data:

Set A-> 1,4,7,8,6   Set B->2,7,5,10; the mean of the differences is the average of the differences of all the paired sets. IE AVERAGE( (2-1) + (7-4) +(5-7)....). This is normally seen within a hypothesis testing scenario. So the Null hypothesis will be Hnull Mean=0; and the alternative hypothesis may be Halternative: Mean<>0. You then compare the T statistic of your data set to that of the T critical value that is set based on your confidence level, and decide whether or not to reject the null. Hope this helps.