Using machine learning to identify important predictors of COVID-19 infection prevention behaviors during the early phase of the pandemic
In the absence of a vaccine or cure, virus containment depended on individual-level compliance with behaviors recommended by the World Health Organization. We used machine learning to identify the most important indicators of compliance, based on a large international psychological survey and on country-level secondary data. The most important indicators were not the “usual suspects,” such as personal threat of virus infection, but rather injunctive norms—namely, the belief that one’s community should engage in such behavior and that society should take restrictive virus-containment measures. People who tend to engage in infection-prevention behaviors also tend to believe that general compliance is necessary to defeat the pandemic, which extends to endorsement of “ought” norms and support for behavioral mandates. These results highlight the potential to intervene by shaping social norms and expectations.