# Enhancing Street-Crossing Safety for Visually Impaired Pedestrians with Haptic and Visual Feedback
## 3 Study 1: Haptic and Visual Feedback for Visually Impaired Pedestrians Crossing at Traffic Signals
### Results
#### 3.2.1 Cross Rate, Decision Time, and User Behavior Data in Study 1  
**Cross rate. **  
We recorded participants' crossing decision under different feedback modes and parameter-combination conditions; \"1\" represented the decision to cross, and \"0\" represented the decision to wait. The main effects were found for frequency (\(\chi^{2}(3)=14.17\), \(p<0.01\)) and size (\(\chi^{2}(2)=12.15\), \(p<0.01\)). Additionally, we observed significant interaction effects between feedback and frequency (\(\chi^{2}(3)=9.44\), \(p<0.05\)) and between feedback and size (\(\chi^{2}(2)=12.35\), \(p<0.01\)). The mean cross rate across feedback modality, frequency, and Size is illustrated in Figure 4a. Post hoc Bonferroni pairwise comparisons showed that the cross rate of frequency 0.5 Hz (0.72) was significantly more than frequency 2.0 Hz (0.27) (\(p<0.05\)) and frequency 4.0 Hz (0.13) (\(p<0.01\)); frequency 1.0 Hz (0.55) was significantly more than frequency 2.0 Hz (0.27) (\(p<0.01\)) and frequency 4.0 Hz (0.13) (\(p<0.01\)). The cross rate of the small size (0.54) was significantly more than that of the large size (0.26) (\(p<0.01\)); the medium size (0.40) was significantly more than the large size (0.26) (\(p<0.01\)). **Decision time. **  
We recorded participants' decision time under different feedback modes and parameter combination conditions, defined as the time interval from receiving the feedback signal to making the final crossing decision. The main effects were found for feedback (\(\chi^{2}(1)=6.71\), \(p<0.05\)), frequency (\(\chi^{2}(3)=40.47,p<0.001\)), and size (\(\chi^{2}(2)=27.35,p<0.001\)). Additionally, we observed significant interaction effects between feedback and frequency (\(\chi^{2}(3)=11.27,p<0.05\)) and between feedback and size (\(\chi^{2}(2)=9.70,p<0.01\)). The mean decision time across feedback modality, frequency, and size is illustrated in Figure 4b. Post hoc Bonferroni pairwise comparisons showed that the decision time of the haptic feedback (4.46 s) was significantly longer than that of the visual feedback (3.66 s) (\(p<0.05\)). The decision time of frequency 4.0 Hz (3.49 s) was significantly faster than that of frequency 0.5 Hz (5.05 s) (\(p<0.01\)) and frequency 1.0 Hz (4.11 s) (\(p<0.05\)); frequency 2.0 Hz (3.67 s) was significantly faster than frequency 0.5 Hz (5.05 s) (\(p<0.01\)) and frequency 1.0 Hz (4.11 s) (\(p<0.01\)); frequency 1.0 Hz (4.11 s) was significantly faster than frequency 0.5 Hz (5.05 s) (\(p<0.01\)). The decision time of the large size (3.61 s) was significantly faster than that of the small size (4.36 s) (\(p<0.5\)) and the medium size (4.18 s) (\(p<0.01\)). **Head rotation angle. **  
We recorded the total head rotation angle during the decision time. The main effect was found for feedback (\(\chi^{2}(1)=16.64,p<0.001\)). The mean head rotation angle across feedback modalities, frequencies, and sizes is illustrated in Figure 5a. Post hoc Bonferroni pairwise comparisons showed that the head rotation angle of the haptic feedback (8.04 degrees) was significantly longer than that of the visual feedback (5.27 degrees) (\(p<0.01\)). **Head movement distance. **  
We recorded the total head movement distance during the decision time. The main effect was found for feedback (\(\chi^{2}(1)=27.78,p<0.001\)), frequency (\(\chi^{2}(3)=24.55\), \(p<0.001\)), and size (\(\chi^{2}(2)=11.06,p<0.01\)). Additionally, we observed significant interaction effects between feedback and size (\(\chi^{2}(2)=7.48,p<0.05\)). The mean total head movement distance across feedback modalities, frequency, and size is illustrated in Figure 5b. Post hoc Bonferroni pairwise comparisons showed that the total head-movement distance of the haptic feedback (3.81 cm) was significantly longer than that of the visual feedback (1.23 cm) (\(p<0.01\)). Figure 4: Mean cross rate and decision time. (**a**) Mean cross rate; (**b**) mean decision time. We also recorded the head movement distance along X, Y, and Z dimensions. For the X dimension, the main effects were found for feedback (\(\chi^{2}(1)=11.09,p<0.001\)).