It can be easy to make errors while calculating both descriptive and inferential statistics. One way to avoid losing marks through small errors is to look at your answer and compare it with the raw data. Does it make sense? If the majority of scores in one data set are bigger than the scores in the other you would expect the mean to be larger for this group. If it isn’t maybe you have made an error when adding all the raw scores together or divided by the wrong number. Always check your answers with care.