We tested a novel extension to mailed invitations to a web-push survey, using a postcard invitation to deliver a scratch-off giftcode incentive similar to an instant-win lottery ticket. Scratch-off postcards were included as one of five conditions in randomized survey experiment varying two mailing types (letter and postcard) and three incentive types (prepaid cash, prepaid giftcodes, and conditional giftcodes). Invitations were sent to a sample of 17,808 addresses in Boston, Massachusetts, recruiting for a new online panel study of city residents. We report response rates and costs for each condition. Findings suggest that letters achieve higher response rates than postcards and are more cost effective overall. We also find that conditional incentives achieve higher response rates and are more cost effective, although conflating factors do not permit clear inferences. Notably, the novel scratch-off postcard condition achieved the lowest response rate and the highest costs per completed survey.

我们对网络推送调查的邮寄邀请进行了新的扩展测试，使用明信片邀请来提供类似于即时中奖彩票的刮刮礼品代码激励。刮开明信片被列为随机调查实验中的五个条件之一，其中有两种邮寄类型（信件和明信片）和三种激励类型（预付现金、预付礼品代码和有条件的礼品代码）。邀请函被发送到马萨诸塞州波士顿的 17,808 个地址样本，以招募新的城市居民在线小组研究。我们报告每种情况的响应率和成本。调查结果表明，信件的回复率高于明信片，总体而言更具成本效益。我们还发现有条件的激励措施可以实现更高的响应率并且更具成本效益，尽管混淆因素不允许明确的推论。值得注意的是，新颖的刮刮明信片条件实现了最低的响应率和最高的每次完成调查的成本。