Rebate Versus Matching, Again: How Opt-in Reshapes the Effectiveness of Price-Equivalent Subsidies

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

Traditional theory predicts equivalent effects of matching and rebate subsidies at equal prices, yet experiments favor matching. Refinements narrow this gap but retain compulsory assignment; take-up is voluntary in practice. We test this implementation margin in a nationwide, incentivized donation experiment with 2,400 Japanese adults, crossing subsidy type and assignment rule. After equalizing budget constraints and accounting for comprehension, total giving is indistinguishable under compulsory assignment. Under opt-in, the matching advantage re-emerges and nearly quadruples because rebate loses effectiveness. LATE estimates suggest advantageous selection into matching but disadvantageous selection into rebate. Self-selection can reshape the policy ranking of price-equivalent instruments.

ディスカッションペーパー

• [最新版] arXiv, 2026. [Full-text link]
• CiDER Discussion Paper（大阪大学感染症総合教育研究拠点）, 2023. [本文リンク]