Prediction indicators for voluntary carbon-offset purchases among trail runners.

Voluntary carbon offsets (VCOs) represent a rapidly growing tool for addressing climate change, but few, if any, studies have focused on predictors of VCO purchasing behavior in association with sport events. Data for this exploratory study were collected from race registration records and interpolated from the U.S. Census. This paper uses multivariate regression analysis to predict VCO purchases among trail runners. We found females, older participants, participants running longer events, and participants living in communities in which people had high education levels relative to income were more likely to purchase VCOs. Purchasing a VCO appeared to be a household level decision because across trail races and years, matching VCO purchasing behavior was 20% higher within households than for individual runners who participated in multiple races. Real time online publishing of VCO purchasers’ names did not increase VCO purchases. Our findings suggest runners motivated by affiliation were more likely to purchase VCOs, and that descriptive (based on what others do) norms had little impact on purchasing behaviors. Efforts to promote VCOs should target subjective norms and households instead of individuals.