共同研究者： 佐々木周作（大阪大学）・ 石原卓典（京都先端科学大学）

要約

Standard economic theory predicts that matching and rebate will have the same effect on individuals’ donation behavior when the donation price is equivalent. However, several experimental studies have reported that their donation behaviors are promoted under matching more than under rebate. This study reveals how treatment effects of matching and rebate change when people can self-select whether to use such schemes or not. Although traditional experimental studies have measured the causal effects of mandatory policy assignment, real-world policies are often applied to only those who accept them. We conduct an incentivized nationwide experiment on 2,400 Japanese residents with four treatments, two 1:1 matching treatments (compulsory / self-selection) and two 50% rebate treatments (compulsory / self-selection), and provide the following findings: Initially selected amount under the compulsory matching is smaller than under the compulsory rebate, while total amount donated to the charity under the former scheme is larger than that under the latter scheme, which is consistent with the existing theories. The treatment effect on the total donation amount among those who self-select to receive the treatment is still larger under the matching scheme than under the rebate scheme, but this difference is further larger than that in the case when using compulsory treatments. The superiority of matching over rebate for the total donation amount becomes more pronounced in the case with a self-selection process.

ディスカッションペーパー

• CiDER Discussion Paper（大阪大学感染症総合教育研究拠点）, 2023. [本文リンク]