Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
This paper studies contributions and punishments in a linear public good game, where group members have different sources of endowment. We compare the behavior of homogeneous groups, in which subjects are exogenously assigned the same endowments, with that of heterogeneous groups, in which half the group members have to exert effort to earn their endowments (effort subjects) and the other half are endowed with a windfall of equal value (windfall subjects).