Social influence during public crises: Weekly dynamics and adaptive patterns of conformity to the collective following the COVID-19 outbreak.

Regional collectivism has been observed to contribute to better coping with public crises such as the COVID-19 pandemic. This study poses a reverse question: Does the eruption of public crises increase people's conformity to the collective? To answer this question, we analyzed real-world transactions on Taobao (the largest e-commerce platform in China), each with a purchase decision and a list of candidates considered before purchasing. Conformity to the collective was measured using two indicators: whether the decision-maker opted for the A) most-sold and B) best-rated options within the candidate option set. The results reveal that both conformity variables were significantly higher in the 10 wk subsequent to January 19, 2020 (when the nationwide COVID-19 crisis erupted in China), than in the 8 wk prior. These shifts were common across subpopulations, regions, and product categories and remained significant after strictly matching across weeks and after using a within-person, longitudinal sample. These shifts were more confidently attributed to the pandemic by further conducting difference-in-differences analyses to compare pandemic-affected regions with their unaffected, comparable counterparts using data from six subsequent regional waves in China. Furthermore, regions with larger increases in conformity during the early stage of the pandemic achieved better antipandemic outcomes. These findings provide real-world evidence for previous theories on behavioral immune systems, terror management, and compensatory control. Additionally, cross-regional comparisons of effect sizes offer exploratory insights into cultural psychology. In summary, these findings capture how human societies dynamically adjust their values to better adapt to unanticipated survival challenges.