Overcoming the J-shaped distribution of product reviews
Hu, Zhang and Pavlou report that product reviews from recent buyers are overwhelmingly positive. Using books, DVDs and videos at two large online retailers collected in 2005, they found that 72 to 78 per cent of products had ratings of four stars or more. The skew persisted with over 2,000 reviews per product, so small samples did not explain it. They argue the average rating is a poor proxy for quality and sales and that the J-shaped pattern stems from biases in review systems. Communications of the ACM 52(10), 144-147, 2009.
Hu, Zhang and Pavlou report that product reviews from recent buyers are overwhelmingly positive. Using books, DVDs and videos at two large online retailers collected in 2005, they found that 72 to 78 per cent of products had ratings of four stars or more. The skew persisted with over 2,000 reviews per product, so small samples did not explain it. They argue the average rating is a poor proxy for quality and sales and that the J-shaped pattern stems from biases in review systems. Communications of the ACM 52(10), 144-147, 2009.
Written from the abstract, OpenAlex, 2026-11-03; full text not read.
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Hu, N., Zhang, J., & Pavlou, P. A. (2009). Overcoming the J-shaped distribution of product reviews. Communications of the ACM, 52(10), 144-147. doi:10.1145/1562764.1562800 https://doi.org/10.1145/1562764.1562800