We examine the effect of consumer reviews on relative sales of books on Amazon.com and BarnesandNoble.com. We find that 1) reviews are overwhelmingly positive at both sites, but there are more reviews and longer reviews at Amazon.com, 2) an improvement in a book's reviews leads to an increase in...

Search frictions can explain why the "law of one price" fails in retail markets and why even firms selling commodity products have pricing power. In online commerce, physical search costs are low, yet price dispersion is common. We use browsing data from eBay to estimate a model of consumer...

Despite substantial efforts to help consumers search in more intuitive ways, text search remains the predominant tool for product discovery online. In this paper, we explore the effects of visual and textual cues for search refinement on consumer search and purchasing behavior. We collaborate...

We study whether Amazon engages in self-preferencing on its marketplace by favoring its own brands (e.g., Amazon Basics) in search. To address this question, we collect new micro-level consumer search data using a custom browser extension installed by a panel of study participants. Using this...

We present a model where social media platforms offer plans that intermix entertaining content with digital advertising ("ads"). Users derive utility from entertainment and learn about their valuation for a product from ads. While some users are fully rational, others naïvely perceive digital...

We investigate the informativeness of hygiene signals in online reviews, and their effect on consumer choice and restaurant hygiene. We first extract signals of hygiene from Yelp. Among all dimensions that regulators monitor through mandated restaurant inspections, we find that reviews are more...

Digitization has led to product proliferation, straining traditional institutions for product discovery; but digitization has also spawned crowd-based rating systems. We compare the relative impacts of professional critics and crowd-based Amazon star ratings on consumer welfare in book...

This paper examines a model in which advertisers bid for "sponsored-link" positions on a search engine. The value advertisers derive from each position is endogenized as coming from sales to a population of consumers who make rational inferences about firm qualities and search optimally....

The financial motivation to earn advertising revenue by spreading misinformation has been widely conjectured to be among the main reasons misinformation continues to be prevalent online. Research aimed at reducing the spread of misinformation has so far focused on user-level interventions with...

Research on the causal effects of online advertising on consumer welfare is limited due to challenges in running large-scale field experiments and tracking effects over extended periods. We analyze a long-running field experiment of online advertising in which a random 0.5% subset of all users...