A psychologist is interested in whether working memory is influenced by sleep loss. The psychologist administers a pre-test measure of working memory to a group of subjects at 8 A.M. on Day One of the study and then administers a post-test measure of working memory at 8 A.M. on Day Two of the study, after keeping the subjects awake the entire night. The psychologist wants to know whether sleep loss affects working memory. What is the statistical analysis we would perform to answer this question