A recent econometric literature shows two distinct paths for identification with shift-share instruments, leveraging either many exogenous shifts or exogenous shares. We present the core logic of both paths and practical takeaways via simple checklists. A variety of empirical settings illustrate...

Many studies use shift-share (or "Bartik") instruments, which average a set of shocks with exposure share weights. We provide a new econometric framework for such designs in which identification follows from the quasi-random assignment of shocks, allowing exposure shares to be endogenous. This...

We develop new tools for causal inference in settings where exogenous shocks affect the treatment status of multiple observations jointly, to different extents. In these settings researchers may construct treatments or instruments that combine the shocks with predetermined measures of shock...

How much do consumption patterns matter for the impact of international trade on inequality? In neoclassical trade models, the effects of trade shocks on consumers' purchasing power are governed by the shares of imports in consumer expenditures, under no parametric assumptions on preferences and...

When estimating the effects of treatments defined by complex formulas, researchers often use simple functions of exogenous shocks as instruments. A leading example is "simulated instruments" for public policy eligibility, which capture variation in state-level policy generosity. We show how more...

Many studies in economics use instruments or treatments which combine a set of exogenous shocks with other predetermined variables by a known formula. Examples include shift-share instruments and measures of social or spatial spillovers. We review recent econometric tools for this setting, which...

Recent work shows that popular partially-linear regression specifications can put negative weights on some treatment effects, potentially producing incorrectly-signed estimands. We counter by showing that negative weights are no problem in design-based specifications, in which low-dimensional...

Digital technology is reshaping workplaces by enabling spatial separation of offices, known as telework, or remote intelligence (RI), and by facilitating automation of service sector tasks via artificial intelligence (AI). This paper is a first attempt to empirically investigate whether AI and...

This paper explores role of product adding and dropping within manufacturing firms over the business cycle. While a substantial body of work has explored the importance of the extensive margins of firm entry and exit in employment and output flows, only recently has research begun to examine the...

This paper applies a novel empirical approach to characterising the horizontal-ness and vertical-ness of affiliates based on Yeaple's complex FDI concept. In its simplest form, horizontal-ness is measured as affiliates' local sales share while their vertical-ness is measures as their share of...