Leader-Selection Mechanisms and Matching Protocols in Public Goods Games: Evidence from the Laboratory.

Using a controlled online laboratory experiment, we investigate how leader-selection rules influence public goods provision under fixed matching and random rematching. In our design, a leader is a first mover who chooses a contribution before the other group members, and this contribution is revealed to the later mover(s) before they make their own decisions. In leaderless groups, all group members choose their contributions simultaneously, so no member observes another member's contribution before deciding. Leadership does not produce a uniform increase in contributions. Among the mechanisms examined, delegated leadership by a randomly selected candidate (DL-RC) exhibited the lowest overall mean contribution, particularly under random rematching; however, the primary analyses did not establish a statistically significant general mechanism effect. Within VL-RC, the accepted one-leader branch exhibited higher observed contributions than the refusal-contingent leaderless branch; within DL-RC, the accepted one-leader branch exhibited higher observed contributions than the refusal-contingent three-first-mover branch. Because these realized branches are generated by candidates' acceptance decisions, the comparisons are conditional and do not identify causal effects of acceptance, refusal, leader absence, or the number of first movers. Across leader-present states, later-mover contributions were positively associated with the observed mean contribution of the first mover(s). Fixed matching yielded a higher observed mean contribution than random rematching, but the pooled difference was not statistically significant; the clearest differences in matching protocols arose in DL-RC.