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Chapter 4: Q 85. (page 259)

Room temperature and dexterity An expert on worker performance is interested in the effect of room temperature on the performance of tasks requiring manual dexterity. She chooses temperatures of 70°Fand 90°Fas treatments. The response variable is the number of correct insertions, during a 30-minute period, in a peg-and-hole apparatus that requires the use of both hands simultaneously. Each

subject is trained on the apparatus and then asked to make as many insertions as possible in 30 minutes of continuous effort.

(a) Outline a completely randomized design to compare dexterity at70° and 90°. Twenty subjects are available.

(b) Because individuals differ greatly in dexterity, the wide variation in individual scores may hide the systematic effect of temperature unless there are many subjects in each group. Describe in detail the design of a matched pairs experiment in which

Short Answer

Expert verified

(a) Twenty subjects are randomly assigned into two groups of ten each, treatments at two different temperature are applied to each group and results are compared.

(b) It can be done when both devices uses machine twice with both temperatures. Order is randomized per subject.

Step by step solution

01

Given Information

An expert on worker performance is interested in understanding the effect of room temperature on task performance requiring manual dexterity.

Each subject is trained on apparatus and asked to make as many insertions as possible in30minutes of continuous efforts.

02

To outline a completely randomized design to compare dexterity at 70°and 90°.

  • Assign twenty subjects randomly to two groups of ten subjects each.
  • Give treatment at 70°to one group and 90°to other group.
  • Compare the number of correct insertions.
03

To describe in detail the design of a matched pairs experiment in which each subject serves as his or her own control.

Since an expert on worker performance is interested in understanding the effect of room temperature on task performance requiring manual dexterity. In matched pair experiment, each subject serves his/her own control can be explained if each subject is using machine twice, at both temperatures. Order of usage is randomized per subject at different temperatures.

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