A Psychologist Would Like to Examine the Effects of Different

question 19

Essay

A psychologist would like to examine the effects of different testing methods on the final performance of college students. One group has regular quizzes, one group has three large exams, and the third group only has a final exam. At the end of the course, the psychologist interviews each student to get a measure of the student's overall knowledge of the material.
a. Do these data indicate any significant differences among the three methods? Test with α = .05.
b. Compute Tukey's HSD to determine exactly which methods are significantly different.
$$\begin{array} { c c c l } \hline \text { Quizzes } & \text { Exams } & \text { Final Only } \\\hline 4 & 1 & 0 & \\6 & 4 & 2 & G = 36 \\3 & 5 & 0 & \Sigma X ^ { 2 } = 164 \\7 & 2 & 2 & \\\hline T = 20 & T = 12 & T = 4 & \\S S = 10 & S S = 10 & S S = 4 &\end{array}$$

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Definitions:

Variable Overhead

Costs incurred during production that fluctuate with production volume, such as utilities or materials.

Total Variable Overhead Variance

The difference between actual variable overhead costs and the expected (standard) costs for the same period.

Direct Labor Efficiency Variance

The difference between the actual hours worked and the standard hours expected, multiplied by the standard labor rate, indicating the efficiency of labor used in production.

Direct Labor Costs

Direct labor costs are the wages and benefits paid to employees who are directly involved in the production of goods or services, constituting part of the total manufacturing costs.