# Visual and Haptic Guidance for Enhancing Target Search Performance in Dual-Task Settings
## 4 Study 2: Visual-Haptic Guidance Design and Evaluation
### Results
#### 4.2.1 Selection Time and User Behavior Data in Primary Task of Study 2  
Selection Time Main effects were found for Row \((F_{2.09,23.03}=9.31,p<0.001)\) and Column \((F_{4,44}=19.62,p<0.001)\). (The sphericity assumption was not met so the Greenhouse-Geisser correction was applied; the corrected degrees of freedom are shown). No interaction effect was found. The mean selection times across Feedback Modality, Row, and Column are illustrated in Figure 6a. Post hoc Bonferroni pairwise comparisons showed that the selection time of row 5 (3.13 s) was significantly slower than those of row 2 (2.60 s) \((p<0.01)\), row 3 (2.51 s) \((p<0.01)\), and row 4 (2.72 s) \((p<0.05)\).  
The selection time of column 1 (3.01 s) was significantly slower than those of column 2 (2.54 s) \((p<0.01)\), column 3 (2.59 s) \((p<0.05)\), and column 4 (2.60 s) \((p<0.001)\); column 5 (3.06 s) was significantly slower than column 2 (2.54 s) \((p<0.001)\), column 3 (2.59 s) \((p<0.01)\), and column 4 (2.60 s) \((p<0.001)\).  
Head Rotation Angle Main effects were found for Row \((F_{2.12,23.33}=5.34,p<0.05)\) and Column \((F_{4,44}=8.58,p<0.001)\). (The sphericity assumption was not met so the Greenhouse-Geisser correction was applied; the corrected degrees of freedom are shown). No interaction effect was found. The mean angles across Feedback Modality, Row, and Column are illustrated in Figure 6b.  
Post hoc Bonferroni pairwise comparisons showed that the head rotation angles of row 2 (66.40 degrees) and row 3 (61.37 degrees) were significantly smaller than that of row 5 (84.92 degrees) \((p<0.05)\), and that the head ration angles of column 2 (64.31 degrees), column 3 (67.79 degrees), and column 4 (64.49 degrees) were significantly smaller than that of column 5 (82.95 degrees) \((p<0.05)\).  
Head Movement Distance Main effects were found for Row \((F_{4,44}=5.21,p<0.05)\) and Column \((F_{4,44}=6.65,p<0.001)\). Post hoc Bonferroni pairwise comparisons showed that the total head movement distance of row 5 (15.69 cm) was significantly longer than that of row 3 (11.76 cm) \((p<0.05)\), and that column 1 (15.02 cm) and column 5 (15.43 cm) were significantly longer than column 4 (12.41 cm) \((p<0.05)\).  
We also recorded the head movement distance along the X, Y, and Z dimensions. For the X dimension, main effects were found for Row \((F_{4,44}=3.22,p<0.05)\) and Column \((F_{4,44}=9.04,p<0.001)\); post hoc Bonferroni pairwise comparisons showed that the distance along the X dimensions of column 1 (8.69 cm) and column 5 (8.90 cm) were significantly longer than those of column 2 (6.69 cm) and column 4 (6.93 cm) \((p<0.05)\).  
For the Y dimension, main effects were found for Row \((F_{4,44}=8.66,p<0.001)\) and Column \((F_{2,06,22,62}=8.47,p<0.001)\). (The sphericity assumption was not met so the Greenhouse-Geisser correction was applied; the corrected degrees of freedom are shown.)Post hoc Bonferroni pairwise comparisons showed that the head movement distance along the Y dimension of row 5 (7.06 cm) was significantly longer than those of row 2 (5.17 cm), row 3 (5.06 cm), and row 4 (5.74 cm) \((p<0.05)\), and that the head movement distance along the Y dimension of column 5 (6.61 cm) was significantly longer than those of column 2 (5.27 cm), column 3 (5.30 cm), and column 4 (5.23 s) \((p<0.05)\), and the distance along the Y dimension of column 1 (6.38 cm) was significantly longer than that of column 4 (5.23 cm) \((p<0.05)\).  
For the Z dimension, a main effect was found for Row \((F_{4,44}=3.79,p<0.05)\). Post hoc Bonferroni pairwise comparisons showed that the head movement distance along the Z dimension of row 5 (7.44 cm) was significantly longer than that of row 3 (5.71 cm) \((p<0.05)\).  
Figure 6: Mean selection time, head rotation degree, and head movement distance results of Primary Task in Study 2.  
The mean head movement distances across Feedback Modality, Row, and Column are illustrated in Figure 6.