Proenvironmental intentions: The case of commuting-mode choice

This article addresses the need for systematic theory comparison and devel-opment in environmentally significant behavior (ESB) research. Using logis-tic regression (N = 398), models based on Schwartz’s norm-activation theory (NAT) and Ajzen’s theory of planned behavior (TPB) were compared as explanations of drivers ’ intentions to reduce or maintain their car use for commuting. NAT explained more variance (McFadden R2 =.342). A model using NAT and TPB constructs was also tested. This explained more variance than either individual theory (McFadden R2 =.379). A personal-normative variable (NAT) and perceived behavioral control (TPB) were the only statisti-cally-significant predictors of intentions in the model derived from both theo-ries. It is argued that combining NAT and TPB constructs accounts for a range of influences on car-use intentions that neither individual theory fully cap-tures. A combined model may also apply to other ESBs, especially those per-ceived as reducing personal utility (i.e., entailing sacrifice)