Predicting why people engage in pro-sustainable behaviors in Portland Oregon: The role of environmental self-identity, personal norm, and socio-demographics.

This study aims to identify factors influencing people's participation in frequent and effective pro-sustainable behaviors (PSB) in Portland, Oregon, using value-belief-norm theory and a modified value-identity-personal-norm (VIP) model. Drawing from a resident survey (n = 484) and applying a series of regression and mediation analyses, we tested the power of the VIP model in our sample to examine the influence of values, environmental self-identity, and personal norms on PSB while adjusting for socio-demographic factors. Our study revealed participants who held altruistic values (i.e., cared for the community, valued diversity and gender equality, and made decisions based on cooperation) had stronger environmental self-identity characterized by a belief that reflects biocentrism, ecofeminism, ecospirituality, or deep ecology. These identities were significantly associated with participation in more effective PSB after adjusting for personal norms. Participants with egoistic values had stronger anthropocentric identity and weaker personal norms which translated into lower participation in more effective PSB. Also, education increased PSB, with master's degree holders participating more than other groups. Overall, values, environmental self-identity, and higher education predicted participation in effective PSB. Our refined theoretical model is, therefore, promising for assessing multiple PSB at once, especially those that significantly reduce carbon footprint on the planet.