Journal
MARKETING SCIENCE
Volume 41, Issue 5, Pages 896-921Publisher
INFORMS
DOI: 10.1287/mksc.2022.1353
Keywords
word of mouth; electronic commerce; retailing
Categories
Funding
- Morrison Center for Marketing Research
Ask authors/readers for more resources
This study examines the market for fake product reviews on Amazon.com and finds that a wide range of products purchase these fake reviews, including those with high ratings. Buying fake reviews leads to a short-term increase in ratings and reviews. The manipulation of ratings has a significant impact on sales and is primarily used by low-quality products.
We study the market for fake product reviews on Amazon.com. Reviews are purchased in large private groups on Facebook and other sites. We hand-collect data on these markets and then collect a panel of data on these products' ratings and reviews on Amazon, as well as their sales rank, advertising, and pricing policies. We find that a wide array of products purchase fake reviews, including products with many reviews and high average ratings. Buying fake reviews on Facebook is associated with a significant but shortterm increase in average rating and number of reviews. We exploit a sharp but temporary policy shift by Amazon to show that rating manipulation has a large causal effect on sales. Finally, we examine whether rating manipulation harms consumers or whether it is mainly used by high-quality products in a manner like advertising or by new products trying to solve the cold-start problem. We find that after firms stop buying fake reviews, their average ratings fall and the share of one-star reviews increases significantly, particularly for young products, indicating rating manipulation is mostly used by low-quality products.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available