
Concept explainers
Terrain Visualization A study was conducted to determine the effect of two lactors on terrain visualization training for soldiers.4 During the raining programs. participants viewed contour maps of various terrains and then were permitted to view a computer reconstruction of the terrain as it would appear from a specified angle. The two factors investig ated in the experiment were the participants’ spatial abilities (abilities to visualize in three dimensions) and the viewing procedures (active or passive). Active participat ion permitted participants to view the computer— generated reconstructions of the terrain from any and all angles. Passive participation gave the participants a set of preselected reconstructions of the terrain. Participants were tested according to spatial ability, and from the test scores 20 were categorized as possessing high spatialability. 20 medium. and 20 low. Then 10 participants within each of these groups were assigned to each of the two training
a. Explain how the authors arrived at the degrees of freedom shown in the ANOVA table.
b. Are the F-values correct?
c. Interpret the test results. What are their practical implications?
d. Use Table 6 in Appendix I to approximate the p-values for the F statistics shown in the ANOVA table.
Source: H.F. Barsam and Z.M. Simutis. “Computer-Based Graphics for Terrain Visualization Training. Human Factors, no. 26, 1984. Copyright 1984 by the Human Factors Society. Inc. Reproduced by permission.

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Chapter 11 Solutions
Introduction to Probability and Statistics
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