Critique each of the following proposed research plans. Your critique should explain any problems with the proposed research and describe how the research plan might be improved. Include any discussion of any additional data that need to be collected. A researcher is interested in determining whether a large aerospace firm is guilty of gender bias in setting wages. To determine potential bias, the researcher collects salary and gender information for all the firm's engineers. The researcher then plans to conduct a "difference in means" test to determine whether the average salary for women is significantly less than the average salary for men. Which of the following variables are likely useful to add to the regression to control for important omitted variables? (Check all that apply)

According to the given info the difference in means test is too limited because it does not include the type of engineer, education level or experience. The gender with lower wages of might be reflected in the type of engineer or education level.

The research could be improved using additional data on the factors namely gender, education, education and the type of engineer.

Then, further it is recommended to construct a multiple regression where the dependent variable is a wage and the four factors are independent variables. The importance of the omited variable by the means of that the "difference in means" test in unsuitable for determining the gender bias in setting wages.