We analyze a large-scale randomized field experiment in which a search engine varied the prominence of search ads for 3.3 million US users: one group of users saw the status quo, while the other saw a lower level of advertising (with prominence of search ads decreased). Revealed preference data...

This paper introduces a model of limited consumer attention into an otherwise standard new trade theory model with love-of-variety preferences and heterogeneous firms. In this setting, we show that trade liberalization needs not be welfare enhancing if the consumers' capacity to gather and...

A central challenge in estimating the causal effect of TV advertising on demand is isolating quasi-random variation in advertising. Political advertising, which topped $14 billion in expenditures in 2016, has been proposed as a plausible source of such variation and thus a candidate for an...

This paper examines the effects of direct-to-consumer advertising (DTCA) of prescription drugs on doctor choice of drug brands. Using antihistamines as an example, we show that DTCA has little effect on the choice of brand despite the massive DTCA expenditure incurred in this class. In contrast,...

Social advertising uses information about consumers' peers, including peer affiliations with a brand, product, organization, etc., to target ads and contextualize their display. This approach can increase ad efficacy for two main reasons: peers' affiliations reflect unobserved consumer...

Yahoo! Research partnered with a nationwide retailer to study the effects of online display advertising on both online and in-store purchases. We use a randomized field experiment on 3 million Yahoo! users who are also past customers of the retailer. We find statistically significant evidence...

As much as forty percent of social media users have been harassed online, but there is scarce causal evidence of how toxic content impacts user engagement and whether it is contagious. In a pre-registered field experiment, we recruited participants to install a browser extension, and randomly...

Consumers’ purchase decisions can be influenced by others’ opinions, i.e., word-of-mouth (WOM), and/or others’ actions, i.e., observational learning. While information technologies are creating increasing opportunities for firms to facilitate/manage these two types of social interaction,...

Online marketplace designers frequently run A/B tests to measure the impact of proposed product changes. However, given that marketplaces are inherently connected, total average treatment effect estimates obtained through Bernoulli randomized experiments are often biased due to violations of the...

We investigate how consumer word of mouth (WOM) develops over time and in turn influences new product adoption. We develop a dynamic aggregate-level model of WOM development and new product diffusion that explicitly captures consumers’ learning of product quality from both marketing...