市场集中度和总生产率：需求的作用（英）

Market Concentration and Aggregate Productivity: The Role of DemandJeremy PearceandLiangjie WuFederal Reserve Bank of New York Staff Reports, no.1159July2025https://doi.org/10.59576/sr.1159AbstractThis paper studies the relationship between market concentration and aggregateproductivity when firm-level demand emergesfrom past marketing investments.Granular firms may invest in demand both tocomplement their productivity andto amplify market power—this second force can create persistentmismatch betweencustomer capital and productivity. The importance of this mismatch depends on therelative persistence of productivity and demand. Empirically, we find that demand ismore persistent thanproductivity, implying a sizable role for mismatch. This leads tosluggish demand-side adjustment in theface of productivity shocks in the quantifiedmodel. Policies targeting static markup distortions—such asproduction subsidies—can exacerbate excessive marketing and thus are subject to a tradeoff betweenstaticgains and dynamic losses.JEL classification:O31, O32, O34, O41,D22, D43, L11, L13, L22Keywords:firm dynamics, productivity, demand, customer capital, marketcompetition, innovation_________________Pearce: Federal Reserve Bank of New York (email:jeremy.pearce@ny.frb.org).Wu:Einaudi Institute forEconomics and Finance(email:liangjie.wu@eief.it).The authorsthank Tincho Almuzara, Mary Amiti,and Simone Lenzu for helpful comments.This paper presents preliminary findings and is being distributed to economists and other interestedreaders solely to stimulate discussion and elicit comments.The views expressed in this paper are those ofthe author(s) and do not necessarily reflect the position of the Federal Reserve Bank of New York or theFederal Reserve System.Researcher(s)’own analyses calculated (or derived) based in part on data fromNielsen Consumer LLCand marketing databases provided through the NielsenIQ Datasets at the KiltsCenter for Marketing DataCenter at The University of Chicago Booth School of Business.Theconclusions drawn from the NielsenIQ data are those of the researcher(s) and do not reflect the views ofNielsenIQ. NielsenIQ is not responsible for, had no role in, and was not involved in analyzing andpreparing the results reported herein.Any errors or omissions are the responsibility of the author(s).To view the authors’ disclosure statements, visithttps://www.newyorkfed.org/research/staff_reports/sr1159.html. concentration, 1IntroductionHow does market concentration affect aggregate productivity?This question has re-ceived lively discussions in policy circles and recent economic literature (De Loeckeret al., 2020; Olmstead-Rumsey, 2022; Akcigit and Ates, 2023; De Ridder, 2024). However,the role of demand-side characteristics of firms, which is a central driver in the firm-size distribution (Hottman et al., 2016; Foster et al., 2016; Einav et al., 2021), has beenlargely ignored in understanding this concentration-productivity relationship. This pa-per introduces endogenous demand or customer capital investment1Afrouzi et al., 2023) into a model of market concentration, where concentration comesfrom both a skewed firm size dispersion and a finite number ofgranularfirms. We focuson thedynamicsof demand to understand how it interacts with productivity at largefirms.With this framework, we address three questions: Are investments in demandthat drive concentration beneficial or detrimental to aggregate productivity? How doesdemand, as slow-moving capital, affect the response of the aggregate to changes in firmproductivity? How do policies designed to undo distortions from concentration affectthe dynamics of productivity and welfare?This paper addresses these questions by making the following contributions.The-oretically, we introduce a dynamic customer capital investment decision in a model ofgranular firms with heterogeneous productivity and provide a computational tool to an-alyze equilibrium in such an environment. We match the data by modeling concentratedmarkets, e.g., granular firms, with dynamic demand and productivity. Granularity hastwo implications: (i) firms behave strategically, manifesting in variable markups (Atke-son and Burstein, 2008) and strategic interactions in marketing, leading to endogenouspath dependency; (ii) firm-level productivity shocks transmit into aggregate shocks,where the transmission depends on the endogenous demand characteristics.Empiri-cally, guided by the model, we decompose the firm size distribution into demand char-acteristics, cost productivity, and markups. In the data, demand is more persistent thanproductivity. Calibrated to the empirical regularities, we find that endogenous customercapital investment improves efficiency, while the strategic interactions on their own de-crease efficiency. This endogenous investment more than doubles the time it takes forinitial advantages in customer capital to vanish. Policy-wise, there is a tradeoff between1In this paper, we use residual demand a