Knowledge that Transforms

This paper shows that product design shapes search frictions and that intermediaries leverage this channel to increase their rents in the context of the U.S. municipal bond market. The majority of bonds are designed via negotiation between a local government and its underwriter. They are then traded in a decentralized market, where the underwriter often also acts as an intermediary. Exploiting variations in state regulations that limit government officials' conflicts of interest, we provide evidence that the underwriter benefits from designing and trading complex bonds, which induces an increase in search frictions. Interestingly, a simpler bond may not necessarily benefit the government, as bond complexity affords flexibility in debt repayment. Motivated by these findings, we build and estimate a model of bond origination and trading to quantify the welfare implications of a policy mandating bond standardization.

Consumer surplus, the area between the demand curve and the price, plays a key role in many models of trade and growth. Quantifying it typically requires estimating and extrapolating demand curves. This paper provides an alternative approach to measuring consumer surplus by focusing on firms as consumers of inputs. We show that the elasticity of a downstream firm's marginal cost to supplier additions and separations measures the downstream firm's consumer surplus relative to its input costs. Using Belgian data and instrumenting for changes in supplier access, we find that for every 1% of suppliers gained or lost, the marginal cost of downstream firms falls or rises by roughly 0.3%. Our estimates are directly informative about the strength of love‐of‐variety effects and the gains from movements along quality ladders. We use our microeconomic estimates of consumer surplus to assess the macroeconomic importance of supplier additions and separations in a growth accounting framework. We find that supplier churn plausibly accounts for about half of aggregate productivity growth.

We offer a theory of changing dimensions of political polarization based on endogenous social identity. We formalize voter identity as in Bonomi, Gennaioli, and Tabellini (2021), but add parties that compete on policy and spread stereotypes to persuade voters. Parties are historically connected to different social groups, whose members are more receptive to the party messages. An endogenous switch from class to cultural identity accounts for three major changes: (i) growing cultural conflict between voters and parties; (ii) dampening of redistributive conflict, despite rising inequality; (iii) a realignment of lower class voters from the left to the right. The incentive of parties to spread stereotypes is a key driver of identity‐based polarization. Using survey data and congressional speeches, we show that—consistent with our model—there is evidence of (i) and (ii) in the voting realignment induced by the “China Shock” (Autor, Dorn, Hanson, and Majlesi (2020)).

We develop a tractable small‐open‐economy framework to characterize the constrained efficient use of the monetary policy rate, foreign exchange (FX) intervention, capital controls, and domestic macroprudential measures. The model features dominant currency pricing, positive premia on local currency debt arising from financiers' portfolio constraints, and occasionally‐binding external and domestic borrowing constraints. We characterize the conditions under which the traditional prescription—relying solely on the policy rate and exchange rate flexibility—remains sufficient, even in the presence of externalities. By contrast, to manage noise trader flows into and out of the local currency debt market, FX intervention and in some cases capital inflow taxes should be used instead of the traditional prescription. Moreover, if a country faces a mix of local currency premia and external borrowing constraints, we establish that certain regulations to limit FX mismatch may alleviate the external borrowing constraint but exacerbate the local currency premia. Finally, we show that capital controls may dominate domestic macroprudential measures in cases when external shocks trigger stress in domestic housing markets.