Chapter 4.2, Problem 82E

(a)

To determine

To explain how this could lead to confounding.

Explanation of Solution

In the question the Brigham Young University statistics department is performing experiments to compare teaching methods. Suppose we randomly assign two lecturers to use standard technology in their sections and the other two lecturers to use multimedia technology. Thus, different lecturers will have different teaching styles and their teaching styles might affect students’ final exam score. Thus, if we would assign two lecturers to use standard technology and the other two to use multimedia technology then we would not be able to distinguish the technology from the teaching style and thus we cannot be sure that the difference are due to technology.

(b)

To determine

To describe a better design for this experiment.

Explanation of Solution

In the question the Brigham Young University statistics department is performing experiments to compare teaching methods. Thus, a better design would assign each teacher to teach one lecture using standard technology and one using multimedia technology. Thus there would be four blocks, one for each teacher. Variability would be diminished within the blocks because they are taught by the same teacher.