Exploring the spatio-temporal social vulnerability indicators considering the impact of internet accessibility: an example of special region of Yogyakarta, Indonesia during 2019–2022

Social vulnerability assessments aim to improve the understanding of the factors influencing disaster impacts on communities. Recent advances in internet and telecommunications technologies have transformed social interactions and access to services, making internet accessibility an increasingly relevant factor in vulnerability analysis. This study examines the effects of incorporating internet accessibility into social vulnerability assessment using data from 2019 to 2022. Principal component analysis (PCA) is applied to compare two scenarios: one excluding internet accessibility indicators and one including them. The results show that the composition of indicators within principal components (PCs) varies annually, particularly after internet accessibility is considered. Internet-related indicators tend to show stronger correlations and dominate certain PCs, which can weaken or exclude other indicators with lower correlations. For example, indicators representing low educational attainment (X6) and poverty (X7) exhibited negative loadings in 2020, affecting the calculation of the Social Vulnerability Index (SVI). In some regencies, high values of these indicators were associated with lower SVI values due to changes in indicator composition. The findings demonstrate that integrating internet accessibility captures contemporary social dynamics and significantly influences social vulnerability assessment results.