How does gender affect teaching evaluations? Several researchers addressed this question during the past decade. In one study several female and male professors in the same department with similar backgrounds were selected. A random sample of 100 female students was drawn. Each student evaluated a female professor and a male professor. A sample of 100 male students was drawn and each also evaluated a female professor and a male professor.

The ratings were based on a 4-point scale (where 1 = Poor, 2 = Fair, 3 = Good, and 4 = Excellent). The evaluations were recorded in the following way:

Column 1 = Female student

Column 2 = Female professor rating

Column 3 = Male professor rating

Column 4 = Male student

Column 5 = Female professor rating

Column 6 = Male professor rating

a. Can we infer that female students rate female professors higher than they rate male professors?

b. Can we infer that male students rate male professors higher than they rate female professors?