# Integrating Decentralized Indoor Evacuation with Information Depositories in the Field
## 6 Discussion
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Evaluation Factor** & **Comparison Base** & **NoDepot** & **DepotSt** & **DepotCr** & **FadingMemory** \\ \hline \multirow{4}{*}{Success Rate} & NoDepot & – & 11 (4.4) & 3 (1.3) & 29 (6.1) \\  & DepotSt & 2 (2.0) & – & 5 (1.6) & 29 (5.1) \\  & DepotCr & 0 (0.0) & 11 (4.4) & – & 29 (6.0) \\  & FadingMemory & 6 (3.0) & 12 (2.8) & 6 (3.2) & – \\ \hline \multirow{4}{*}{Evacuation Time} & NoDepot & – & 27 (70.5) & 10 (14.6) & 16 (120.4) \\  & DepotSt & 1 (1.0) & – & 5 (25.6) & 12 (68.4) \\  & DepotCr & 0 (0.0) & 24 (75.0) & – & 16 (117.4) \\  & FadingMemory & 5 (24.2) & 13 (72.0) & 9 (14.3) & – \\ \hline \multirow{4}{*}{Situation Awareness} & NoDepot & – & 100 (15.4) & 77 (4.3) & 33 (5.5) \\  & DepotSt & 0 (0.0) & – & 2 (1.5) & 4 (8.0) \\  & DepotCr & 0 (0.0) & 98 (12.4) & – & 9 (11.0) \\ \cline{1-1}  & FadingMemory & 20 (3.1) & 96 (15.1) & 60 (5.1) & – \\ \hline \hline \end{tabular}
\end{table} 
Table 12: Comparisons among different evacuation strategies in three dimensions: success rate, evacuation time, and situation awareness. Each figure represents the number of simulated emergency cases where the evacuation strategy is advantageous over the evacuation strategy in the comparison base because of saving more evacuees (the number of the more evacuees saved per case in parentheses), or because it has saved the same number of evacuees but has consumed less time (the number of the fewer steps used per case in parentheses), or because it has allowed more edge updates (the number of the more updated edges per case in parentheses). The total number of simulated emergency cases is one hundred. decreased evacuation steps. In very few cases, such improvements of situation awareness may still accidentally lead to decreased evacuation success due to the effect of non-linear interactions between different evacuees, and the interactions between evacuees and the dynamically changing environment. This also explains why there are more cases where integrating information depositories has increased edge updates and decreased evacuation steps, but less so many cases where integrating information depositories has saved more people. Compared with the significant improvements by deploying information depositories at staircases, depositories in corridors have made less significant improvements. The comparison of the Wilcoxon signed-rank tests for DepotSt and DepotCr also indicates that the information depositories should be strategically distributed. Simulation results suggest information depositories at staircases lead to better evacuation outcome than information depositories in corridors. Compared with corridors where evacuees' route choices are largely restricted, staircases may allow evacuees to have more alternatives towards the exits and more likely to make decisions that have a significant impact on the evacuation outcome. A combined depository scenario of DepotSt and DepotCr shares the advantages and disadvantages on both sides. Comparison of evacuation success between a combined depository scenario and DepotSt suggests that increased number of depositories leads to more evacuation success. The fading memory, as another approach to bridging the temporal gap of knowledge exchange in decentralized evacuations, has also improved the evacuation success significantly. Compared with DepotSt, fading memory has improved the evacuation success in a larger number of cases (29 cases), and has a larger average success rate (83.7). At the same time, in more cases (6 cases), it has saved fewer evacuees than DepotSt (2 cases), which fundamentally attributes to the mechanism of fading memory model per se: Fading memory devalues older knowledge because of losing trust in its continuing validity, which involves risks of devaluing knowledge that is still valid. In such life-critical situations as evacuations, the uncertainty of leading to fewer people saved should be minimized at strategic level.