## 3 Case Study: Hurricane Irma
### Case Study Results
After 10 September 2017, the daily traffic resilience value for all segments recovered after Hurricane Irma. \begin{table}
\begin{tabular}{c c c c c c c c c c c c c} \hline \hline  & & & **S1** & **S2** & **S3** & **S4** & **S5** & **S6** & **S7** & **S8** & **S9** & **S10** \\  & & **(0350)** & **(0191)** & **(9950)** & **(9953)** & **(0184)** & **(0190)** & **(0225)** & **(0361)** & **(0358)** & **(0320)** \\ \hline \multirow{4}{*}{**Seen**} & \multirow{4}{*}{**Seen**} & 9 April 2017 & 0.834 & 0.814 & 0.782 & 0.609 & 0.780 & 0.744 & 0.726 & 0.826 & 0.839 & 0.811 \\ \cline{2-11}  & & 5 September 2017 & 0.821 & 0.785 & 0.740 & 0.567 & 0.734 & 0.721 & 0.686 & 0.802 & 0.842 & 0.834 \\ \cline{2-11}  & & 6 September 2017 & 0.776 & 0.764 & 0.711 & 0.528 & 0.690 & 0.677 & 0.652 & 0.749 & 0.813 & 0.773 \\ \cline{2-11}  & & 7 September 2017 & 0.750 & 0.747 & 0.695 & 0.504 & 0.672 & 0.643 & 0.624 & 0.719 & 0.791 & 0.697 \\ \cline{2-11}  & & 8 September 2017 & 0.738 & 0.755 & 0.705 & 0.491 & 0.680 & 0.614 & 0.613 & 0.707 & 0.767 & 0.667 \\ \cline{2-11}  & & 9 September 2017 & 0.760 & 0.788 & 0.745 & 0.512 & 0.721 & 0.610 & 0.639 & 0.732 & 0.746 & 0.644 \\ \cline{2-11}  & & 10 September 2017 & 0.794 & 0.819 & 0.781 & 0.577 & 0.761 & 0.659 & 0.689 & 0.770 & 0.776 & 0.688 \\ \cline{2-11}  & & 11 September 2017 & 0.814 & 0.833 & 0.799 & 0.613 & 0.781 & 0.694 & 0.718 & 0.793 & 0.802 & 0.725 \\ \cline{2-11}  & & 12 September 2017 & 0.825 & 0.841 & 0.809 & 0.640 & 0.797 & 0.722 & 0.740 & 0.811 & 0.822 & 0.755 \\ \cline{2-11}  & & 13 September 2017 & 0.831 & 0.846 & 0.814 & 0.650 & 0.806 & 0.736 & 0.749 & 0.820 & 0.834 & 0.774 \\ \cline{2-11}  & & 14 September 2017 & 0.834 & 0.847 & 0.814 & 0.649 & 0.809 & 0.742 & 0.749 & 0.824 & 0.842 & 0.788 \\ \cline{2-11}  & & 15 September 2017 & 0.835 & 0.845 & 0.812 & 0.645 & 0.809 & 0.744 & 0.747 & 0.826 & 0.847 & 0.797 \\ \hline \multirow{4}{*}{**Seen**} & **Segment resilience** & 0.801 & 0.807 & 0.767 & 0.582 & 0.753 & 0.692 & 0.694 & 0.782 & 0.810 & 0.746 \\ \cline{2-11}  & & **Rout Resilience** & & & & & & & & & & \\ (S1-S10) & & & & & & & & & & & & \\ \hline \multicolumn{11}{c}{**Rout Resilience**} & & & & & & & & & & & & \\ (S6-S10) & & & & & & & & & & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Overall route resilience for US I-75 over ten stations. Figure 7: Traffic Resilience for **(a)** Segment S1(0350) and **(b)** US I-75 Route. For each segment, the segment resilience values are obtained from the average daily traffic resilience during the study period of 4-17 September 2017. The segment resilience for Segment 1 (S1) is 0.801. The lowest segment resilience in the evacuation route from S1-S10 is found to be Segment 4 with 0.582, whereas the most resilient segment is Segment 9 with a 0.810 segment resilience value. For travelers who trekked along the evacuation route, their route resilience was bounded by the lowest segment resilience. Considering a person who traveled the entire route from S1-S10, the route resilience is bounded by the least resilient segment (S4) and capped by the most resilient segment (S9), and the average route resilience is around 0.676 along S1-S10. This value can be further interpreted as follows: during the study period of 4-17 September 2017, the traffic condition along US I-75 was 67.6% resilient to the traffic evacuation disturbances posed by Hurricane Irma. For travelers who traveled only part of the evacuation route, for example, from S6-S10, the route resilience was bounded by the least resilient segment (S6), capped by the most resilient segment (S9), and the average route resilience was around 0.745 along S6-S10. Similar concepts and interpretations can be applied to daily traffic route resilience, where the route resilience value is dependent mainly on the least resilient segment and may not be more resilient than the most resilient segment. These results show that the response uncertainty of the travelers was considered when interpreting the route resilience.