A participatory pairwise comparison method for assessing social value of cultural heritage in risk analysis

Natural hazards pose significant risks to cultural heritage, leading to monetary losses and fatalities annually.  Hazard exposure encompasses spatial, quantitative, and qualitative aspects of potentially impacted elements. Cultural heritage necessitates the integration of both intangible and tangible values in risk assessment frameworks for various reasons, including prioritization in the safeguarding of cultural heritage assets and effective risk management. This study introduces a participatory, quantitative approach to evaluate the social value of cultural heritage for the assessment of natural hazard exposure. The research specifically addresses the challenge of incorporating intangible values, particularly social value, into risk assessment. The methodology employs a web-based pairwise comparison survey where participants answer the question "Which among the following cultural heritage items would you recommend to a friend?" for pairs of heritage items. Each item is presented with a photo, name, and brief description, with pairs selected using the Swiss tournament method to maximize item occurrence. The survey platform, developed using open-source tools (Python, Flask, and MariaDB), transforms qualitative preferences into quantitative scores through eigenvalue analysis of the resulting pairwise comparison matrix. The method was applied to Florence historical city center, a UNESCO World Heritage site, where 48 heritage buildings were evaluated through 2379 survey responses from the community of local cultural association members. When combined with flood hazard data, the methodology demonstrated how incorporating social values can substantially alter the spatial distribution of exposure compared to traditional hazard mapping. The methodology provides a replicable tool for assessing intangible values in cultural heritage exposure analysis, though results may vary depending on the participating community. This research contributes to improved risk management and prioritization of mitigation measures by incorporating community-based valuation into intangible exposure assessments.

Acknowledgement:

This work was carried out within RETURN Extended Partnership and received funding from the European Union Next-GenerationEU (National Recovery and Resilience Plan – NRRP, Mission 4, Component 2, Investment 1.3 – D.D. 1243 2/8/2022, PE0000005)