In a natural field experiment conducted in a big grocery chain in Armenia, we test the impact of demand-side behavioral (an environmental nudge) and conventional (financial bonus scheme) policies to curb the purchase of single-use plastic bags. We find that both interventions are effective to reduce the demand for single-use plastic bags. Furthermore, the financial bonus scheme is more powerful than the environmental nudge. However, the financial bonus scheme backfires in the sense that it reduces the visits to the grocery chain resulting in less money spent by an average customer unlike the environmental nudge. We also study, whether customers use the reusable bags received for free and how to motivate them to do so. The findings suggest a strong correlation between reusable bag usage and shopping frequency. While many customers use the bag only once, the more frequent the shopping behavior the higher the usage of the reusable bags. Lastly, financial incentives matter for reusable bag usage.

中文翻译：

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打破塑料袋的习惯：测试减少塑料袋需求的干预措施


在亚美尼亚一家大型杂货连锁店进行的自然田间实验中，我们测试了需求方行为（环境推动）和传统（财务奖励计划）政策对遏制一次性塑料袋购买的影响。我们发现这两种干预措施都有效地减少了对一次性塑料袋的需求。此外，财务奖金计划比环境推动更强大。然而，与环境推动不同，经济奖金计划适得其反，因为它减少了对杂货连锁店的访问，从而减少了普通客户花费的钱。我们还研究客户是否使用免费获得的可重复使用的袋子，以及如何激励他们这样做。研究结果表明，可重复使用的袋子使用与购物频率之间存在很强的相关性。虽然许多客户只使用袋子一次，但购物行为越频繁，可重复使用袋子的使用率就越高。最后，经济激励措施对可重复使用的袋子的使用很重要。