The computer science department plans to offer three introductory - level CS courses for students who have very little computer experience: one using Python, one using Fortran and one using Java.

Question

a) The department chairman plans to give all students the same general programming exam at the end of the year and to compare the relative effectiveness of using each of the programming languages by comparing the mean grades of the students from each course. What is wrong, if anything, with the chairman’s plan?

b) Suppose 300 students wish to take introductory programming. How would you randomly assign 100 students to each of the three courses? Clearly explain how this could be done.

c) Name a lurking variable that all the above methods miss. Be specific.

Answer 1

a) must also compare the scores on the exam to see which

programming language has the most effect upon the exam

b) stratified sampling is one possible strategy....

sort the students by id # or name....

students 1,4,7,10,13,16,19,....298

2,5,8,11,14,17,20,....299

3,6,9,12,15,18,21,....300

c) programming experience

language barrier

problem solving and math skills