Resilience and stakeholder need

Abstract

The current resilience literature lacks a thorough comparison of the behavior of resilience metrics using fundamental models of system performance. To close this gap, this study identifies three metrics that either encompass or can be easily amended to encompass resilience definition of resilience as proposed by Ayyub [1]. The three selected metrics are integral resilience [1], [2], quotient resilience [3], [4], and expected system degradation function [5]. While each of these metrics measures resilience in its own way, gaps exist that affect the metrics' decision-support potential. This study identifies gaps common to these metrics, which limit their decision support value. The gaps include: (1) Lack of consideration of stakeholder performance preferences. (2) Lack of consideration of different stakeholder time horizon. (3) Lack of performance substitution over time. The first step of the study is to modify the three selected metrics to satisfy the broad definition of resilience if necessary. The second step is to develop extended versions of the metric to close the three identified gaps. The third step is to compare the six metrics using a fundamental model of performance and need with known variables (failure time, robustness, recovery time, recovery performance level, etc.). The extended metrics demonstrate different values from the original metrics which are consistent with the spirit of the metrics and largely congruent with intuition.