Three professors at Northern Kentucky University compared two different approaches to teaching courses in the school of business (M. W. Ford, D. W. Kent, and S. Devoto, "Learning from the Pros: Influence of Web-Based Expert Commentary on Vicarious Learning About Financial Markets," Decision Sciences Journal of Innovative Education, January 2007, 5(1), 43-63). At the time of the study, there were 2,100 students in the business school, and 96 students were involved in the study. Demographic data collected on these 96 students included class (freshman, sophomore, junior, senior), age, gender, and major.
a. Describe the population of interest.
b. Describe the sample that was collected.
c. Indicate whether each of the four demographic variables mentioned is categorical or numerical.
d. For each of the four demographic variables mentioned, indicate the measurement scale.