Template-Type: ReDIF-Paper 1.0
Series: Tinbergen Institute Discussion Papers
Creation-Date: 2021-05-17
Number: 21-042/V
Author-Name: Ben Vollaard
Author-Workplace-Name: Tilburg University
Author-Name: Jan C. van Ours
Author-Workplace-Name: Erasmus University Rotterdam
Title: Bias in expert product reviews
Abstract: Hard evidence on bias in expert reviews and its consequences for ratings is rare. This holds particularly true for conflicts of interest that are thought to be common in non-blind product reviews but are not readily observable: ad hoc relationships between reviewers and producers. We present a textbook case of a long-running expert product review in the food service industry for which we happen to know the reviewer's conflict of interest: being affiliated to one particular producer. As is typical, only insiders were aware of the possible source of bias in the review. The review resembles other non-blind tests of product quality. We obtained detailed data to map the consequences of the conflict of interest. We find evidence of a sizable bias in the reviewers' ratings. Our findings suggest that reviewers' ad hoc relationships with producers, often dismissed as `coming with the job', can be very harmful.
File-URL: https://papers.tinbergen.nl/21042.pdf
File-Format: application/pdf
File-Size: 484795 bytes
Handle: RePEc:tin:wpaper:20210042