Page 405 - Sensing, Intelligence, Motion : How Robots and Humans Move in an Unstructured World

380 HUMAN PERFORMANCE IN MOTION PLANNING

TABLE 7.18. Results of ANOVA for Path Length, Experiment Two
ANOVA Effects studied: 1—visibility, 2—day
df MS df MS
Effect Effect Effect Error Error F-Value p-Level
1 1 13860.02 10 7756.985 1.786780 0.210934
2 1 6281.40 10 7292.907 0.861303 0.375232
12 1 12706.58 10 7292.907 1.742321 0.216262

TABLE 7.19. Results of ANOVA on Completion Time, Experiment Two
ANOVA Effects studied: 1—visibility, 2—day

df MS df MS
Effect Effect Effect Error Error F-Value p-Level
1 1 125426.0 10 197945.9 0.633638 0.444509
2 1 0.4 10 442773.8 0.000008 0.997735

12 1 149626.0 10 44273.8 3.379561 0.095856

5. An ANOVA was applied to the independent variable of completion time in
Experiment Two. The variables involved are as follows:

• Dependent variables:
1. Completion time.
• Independent variables:
1. Visibility, with 2 levels: visible and invisible.
2. Day (repeated measures), with 2 levels: day 1 and day 2.

The results are shown in Table 7.19. The p-levels for the main effects and
interaction effect are all larger than the accepted threshold significance level
0.05. Hence all null hypotheses for the main effects and interaction effect are
accepted. We thus conclude that there are no significant effects for the visibility
factor and day (training) factor, and this does not change across all levels of the
independent variables. In other words, surprisingly, neither the visibility factor
nor the day (training) factor has a significant effect on the completion time.
6. The MANOVA was applied to the combined data set. The variables involved
are as follows:

• Dependent variables:
1. Path length.
2. Completion time.