Put a bet on it: Can self-funded commitment contracts curb fitness procrastination?
通过随机实验，研究了自费承诺合同（硬合同与软合同）对1629名健身房会员锻炼行为的影响，发现硬合同显著增加月均健身次数21%，软合同增加8%。
We investigate the use of a highly scalable intervention to help individuals achieve their physical activity goals: self-funded commitment contracts. Using a randomised experiment, we compare the effect of soft (non-incentivised) and hard (incentivised) contracts among 1629 members of a gym in Stockholm, Sweden. We find a significant positive impact of being offered a hard contract on monthly visits to the gym and the probability of meeting one's contract goal. Relative to the control group, being offered a hard contract significantly increases gym visits by 21%, while being offered a soft contract leads to an 8% increase.