What impact will terrorism have on America's cities? Historically, large-scale violence has impacted cities in three ways. First, concentrations of people have an advantage in defending themselves from attackers, making cities more appealing in times of violence. Second, cities often make...

We consider a linear panel event-study design in which unobserved confounds may be related both to the outcome and to the policy variable of interest. We provide sufficient conditions to identify the causal effect of the policy by exploiting covariates related to the policy only through the...

We combine nine previously proposed measures to construct an index of political polarization among US adults. We find that the growth in polarization in recent years is largest for the demographic groups least likely to use the internet and social media. For example, our overall index and eight...

We use a novel retail panel with detailed transaction records to study the effect of the Supplemental Nutrition Assistance Program (SNAP) on household spending. We use administrative data to motivate three approaches to causal inference. The marginal propensity to consume SNAP-eligible food...

We study the problem of measuring group differences in choices when the dimensionality of the choice set is large. We show that standard approaches suffer from a severe finite-sample bias, and we propose an estimator that applies recent advances in machine learning to address this bias. We apply...

We propose a local measure of the relationship between parameter estimates and the moments of the data they depend on. Our measure can be computed at negligible cost even for complex structural models. We argue that reporting this measure can increase the transparency of structural estimates,...

We estimate the effect of information and expertise on consumers' willingness to pay for national brands in physically homogeneous product categories. In a detailed case study of headache remedies we find that more informed or expert consumers are less likely to pay extra to buy national brands,...

News consumption is moving online. If this move fundamentally changes how news is produced and consumed it will have important ramifications for politics. In this chapter we formulate a model of the supply and demand of news online that is motivated by descriptive features of online news...

We study newsworthiness in theory and practice. We focus on situations in which a news outlet observes the realization of a state of the world and must decide whether to report the realization to a consumer who pays an opportunity cost to consume the report. The consumer-optimal reporting...