The Effects of a Platform-Initiated Reviewer Incentive Program on Regular Review Generation

To stimulate product reviews, many large e-commerce platforms have launched reviewer incentive programs in which free products are provided to reviewers in exchange for them generating reviews on the received free products (incentivized reviews). Prior studies explored the effects of incentives on review generation mainly through the comparison between the incentivized reviews and the non-incentivized reviews (regular reviews). In this study, we focus on an unexplored aspect of platform-initiated reviewer incentive programs – the impact of participation in such programs on reviewers' regular reviews. We find that after receiving free products via the program, the reviewers generate 46.03% more regular reviews, increase the regular-review length by 3.40%, and increase the average regular-review rating by 2.18%. We attribute the findings to the norm of reciprocity towards the platform evoked by the received free products. Consistently with our theorization, reviewers change their regular-review activities only after they receive a sufficient number of free products, and the magnitude of the changes is positively moderated by the number of and the monetary values of the received free products. Our results demonstrate that apart from motivating the incentivized reviews, the platform-initiated incentives can also trigger evident changes in the recipients' regular reviews