Abstract
Effort investment is an important barrier that keeps individuals from engaging in pro-environmental behaviors and previous studies revealed that expected cognitive effort can reduce motivation for pro-environmental goals. The current study sought to investigate whether effort changes the shape of the cost-benefit analysis, and in particular whether it leads to stronger discounting of outcome value. The study employed a within-subjects experimental design through an online study (N = 400) using the Work for Environmental Protection Task (WEPT) featuring both pro-environmental and personal outcomes. We assessed participants' binary choice to accept or decline specific trial of a number identification task based on expected effort-reward-outcome combinations. Questionnaires were added to explore inter-individual characteristics. Overall, participants preferred trials with higher reward magnitude, lower effort requirements, and those benefiting them personally. Moreover, pro-environmental outcomes featured more pronounced effort discounting, or in other words, a weaker shielding of effort effects by outcome magnitude. Together, this provides experimental evidence for a general inferiority of pro-environmental outcomes (replicating previous data) and reveals a skewed costs-benefit analysis that prioritizes effort costs over outcome magnitude.