  We conduct a field experiment on a movie-recommendation platform to identify
if and how recommendations affect consumption. We use within-consumer
randomization at the good level and elicit beliefs about unconsumed goods to
disentangle exposure from informational effects. We find recommendations
increase consumption beyond its role in exposing goods to consumers. We provide
support for an informational mechanism: recommendations affect consumers'
beliefs, which in turn explain consumption. Recommendations reduce uncertainty
about goods consumers are most uncertain about and induce information
acquisition. Our results highlight the importance of recommender systems'
informational role when considering policies targeting these systems in online
marketplaces.
