Synergistic and Conflicting Effects of Incentive and Nudge Tools on Public Co-Production Behavior

In coproduction, policy mixes combining incentive-based and nudge-based tools are widely adopted to encourage citizen co-production. However, the micro-mechanisms underlying their synergistic or conflicting effects remain unclear. Grounded in motivation crowding and construal level theories, this study employs a 3×3 vignette experiment to test how the interaction between incentive types (monetary/non-monetary) and nudge frames (concrete/abstract) influences co-production. Results show that while monetary incentives alone significantly promote co-production, non-monetary incentives and nudges show no direct effects. For interaction effects, the combination of monetary incentives and abstract framing leads to significant backfire, whereas non-monetary incentives paired with concrete framing result in weak negative synergy. Regression analyses further confirm these crowding-out patterns. Moreover, the study identifies a distinct interaction effect between the two tool categories.