# Integrating Decentralized Indoor Evacuation with Information Depositories in the Field
## 6 Discussion  
Table 12 shows a summary of the comparisons among different evacuation strategies in three dimensions: success rate, evacuation time, and situation awareness. For the success rate, the figures show the numbers of simulated emergency cases where one evacuation strategy has saved more evacuees than another evacuation strategy, and the figures in parentheses represent the numbers of the more evacuees saved per case. For the evacuation time, the figures are the numbers of simulated emergency cases where one evacuation strategy used less evacuation time than another evacuation strategy, and the figures in parentheses represent the numbers of the fewer steps used per case. For situation awareness, the figures are the numbers of simulated emergency cases where one evacuation strategy has more edge updates than another evacuation strategy, and the figures in parentheses represent the numbers of the more edges updated per case. The evacuation times were computed based on the cases when two evacuation strategies have saved the same number of evacuees but have consumed different evacuation times. Table 13 shows the average success rates and the average edge updates calculated from the total 100 simulated emergency cases. To find out whether the differences of success rates and edge updates between NoDepot and other evacuation strategies are statistically significant, the Wilcoxon signed-rank test has been applied. Figure 15: The number of successful evacuees of each emergency with depositories being deployed at staircases, or applying fading memory. Table 13 shows that the edge updates of DepotSt and DepotCr were significantly different from the edge updates of NoDepot, which means that integrating information depositories has made a significant difference in situation awareness. Table 12 shows that, in all the one hundred simulated emergency events, DepotSt has more edge updates than NoDepot, and DepotCr has improved edge updates in 77% of the simulated emergency events. In no cases, DepotSt or DepotCr has fewer edge updates than NoDepot. It is safe to conclude that integrating information depositories has improved the situation awareness in terms of the edge updates. The Wilcoxon signed-rank test also shows that a significant difference between the success rate of DepotSt and NoDepot was observed. Table 12 shows that deploying information depositories at staircases has guaranteed to save no fewer evacuees in 98% of the simulated emergency events, and to consume no more evacuation time in 99% of the simulated emergency events. It has improved the evacuation results in 38% of the simulated emergency events, either by saving more evacuees (11 simulated emergency cases), or by reducing the evacuation time (27 simulated emergency cases). Noticeably, although DepotSt has more edge updates in all the simulated emergency events than NoDepot, there are still two cases where DepotSt has saved fewer evacuees and one case where DepotSt has increased the evacuation time. This can be explained by the complexity of the evacuation problem per se. Evacuation dynamics is very complex, where multiple factors are involved and interact non-linearly to produce an output shown as features such as the success rate and evacuation time [15]. In some cases, even if the situation awareness has been more current due to the new strategy, such improvements may not always trigger an increased number of successful evacuees or \begin{table}
\begin{tabular}{l c c c c} \hline \hline  & **NoDepot** & **DepotSt** & **DepotCr** & **FadingMemory** \\ \hline Average Success Rate & 82.1 (9.3) & 82.5 * (9.0) & 82.1 (9.3) & 83.7 * (8.6) \\ Average Edge Updates & 100.3 (18.0) & 115.7 * (28.2) & 103.6 * (19.4) & 101.5 (17.5) \\ \hline \hline \end{tabular}
\end{table} 
Table 13: The average success rate and the average edge updates calculated from the total 100 simulated emergency cases. Statistical significant differences (Wilcoxon \(p<\) 0.05) are indicated with (*), and standard deviations are labeled in parentheses.