14. Terrain Visualization A study was conducted to determine the effect of two factors on terrain visualization training for soldiers.5 The two factors investigated in the experiment were the participants’ spatial abilities

(abilities to visualize in three dimensions) and the viewing procedures—active viewing permitted participants to view computer-generated pictures of the terrain from any and all angles, while passive participation gave the participants only a set of preselected pictures of the terrain.

Sixty participants were classified into three groups of 20 according to spatial ability (high, medium, and low), and 10 participants within each of these groups were assigned to each of the two training modes, active or passive. The accompanying tables are the ANOVA table computed by the researchers and the table of the treatment means

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.

Error Source Main effects: Training condition Ability Interaction: Training condition df MS df F P 1 103.7009 54 3.66 .0610 2 760.5889 54 26.87 .0005 Ability Within cells 2 124.9905 54 4.42 .0167 54 28.3015 Training Condition Spatial Ability High Medium Low Active Passive 17.895 9508 5.031 5.648 1.728 1.610 Note: Maximum score = 36.