How Valid Are Social Vulnerability Models?

Abstract

Social vulnerability models are becoming increasingly important for hazard mitigation and recovery planning, but it remains unclear how well they explain disaster outcomes. Most studies using indicators and indices employ them to either describe vulnerability patterns or compare newly devised measures to existing ones. The focus of this article is construct validation, in which we investigate the empirical validity of a range of models of social vulnerability using outcomes from Hurricane Sandy. Using spatial regression, relative measures of assistance applicants, affected renters, housing damage, and property loss were regressed on four social vulnerability models and their constituent pillars while controlling for flood exposure. The indices best explained housing assistance applicants, while they poorly explained property loss. At the pillar level, themes related to access and functional needs, age, transportation, and housing were the most explanatory. Overall, social vulnerability models with weighted and profile configurations demonstrated higher construct validity than the prevailing social vulnerability indices. The findings highlight the need to expand the number and breadth of empirical validation studies to better understand relationships among social vulnerability models and disaster outcomes.

Evaluating social vulnerability indicators: criteria and their application to the Social Vulnerability Index

“…We believe that the best way forward is to allow experts to construct meaningful indicators by specifying variable-specific weights, without reliance on statistical techniques like PCA. Rufat et al (2019) found that this approach performed better than existing indices in explaining Hurricane Sandy outcomes. All indices used for public policy should pass some test of their utility, whether using the criteria we outline or others.…”

“…While social vulnerability indices are widely used, none have been definitively validated. Recent work has shown indicators had little explanatory power in terms of post-hurricane Sandy assistance applications (Rufat et al 2019).…”

Creating a water risk index to improve community resilience

“…Considering all types of hazard events, one study [48] finds that Peacock et al's Community Disaster Resilience Index [49] and Foster's Resilience Capacity Index [50] correlate significantly with economic damages and fatalities, whereas Cutter et al's Social Vulnerability Index [20] correlates significantly with presidential disaster declaration. Another study agrees, suggesting that after controlling for flood exposure, the Social Vulnerability Index may not predict damages and may instead predict housing assistance applicants [51]. However, both of these studies test general indices, as opposed to flood vulnerability or flood risk indices.…”

Spatially Explicit Assessment of Social Vulnerability in Coastal China

“…However, whether the pre-event descriptions correspond to post-disaster outcomes is an ongoing issue. Few attempts to validate the SoVI metric were found, and extreme event losses have been regarded as a frequently proposed approach [40,[90][91][92]. Cutter et al [40] suggested that SoVI in a post-event situation, such as Hurricane Katrina, can be validated by comparing the losses and recovery result of different affected regions with the previously calculated SoVI.…”

“…Cutter et al [40] suggested that SoVI in a post-event situation, such as Hurricane Katrina, can be validated by comparing the losses and recovery result of different affected regions with the previously calculated SoVI. Rufat et al [90] compared the outcomes of Hurricane Sandy with the SoVI constructed by four types of models. However, the correlation coefficients were low.…”