Your client, E.AirPower is a start-up business who provide sustainable energy to their customers. Last year they expanded significantly and hired 100 graduates in their sales force to help them grow their marketing team and client base.

E.AirPower used the XRT© test of intelligence during selection to identify which candidates should be offered the job, following an application form and telephone interview. The XRT© has been designed to measure “fluid intelligence in a way that allows the test user to make excellent predictions about the future job performance of the test taker” (page 4 of the XRT Test Manual). It has been designed to be sensitive to differences in intelligence within a graduate population. The publisher claims that the test is free from adverse impact and has superb test re-test reliability. The test has 50 multiple-choice questions each with only one correct answer (maximum score = 50).

E.AirPower have asked you to evaluate whether the XRT© test is as good as it claims to be, and whether it is a better predictor of job performance than degree class. They have also heard anecdotally that men are more satisfied in their jobs than women, so would like you to investigate whether this is the case with the data available.


You have been given a data file containing data from the 100 successful job applicants. The dataset contains the following variables