Matt Elliott

Professor of Economics, Cambridge University

Fellow, Jesus College

European Research Council (ERC) Sponsored Research

Embedded Markets and the Economy (EMBED) 

(Project ID: 757229) 


Contact Information

Email: mle30 [at] cam.ac.uk

Room: 42

Address: Faculty of Economics, Austin Robinson Building, Sidgwick Avenue, Cambridge, CB3 9DD.

CV


Published and accepted papers

Capability Accumulation and Conglomeratization in the Information Age (Supplementary Appendix) (with Jun Chen and Andrew Koh)

Journal of Economic Theory, forthcoming


Supply Network Formation and Fragility (Supplementary Appendix) (with Ben Golub and Matt Leduc)

American Economic Review, 2022


Investments in social ties, risk sharing and inequality (Supplementary Appendix) (with Attila Ambrus)

Review of Economic Studies, 2021


The importance of social norms against strategic effects: The case of COVID-19 vaccine take up (with Marina Agranov and Pietro Ortoleva)

Economic Letters, 2021


Systemic Risk-Shifting in Financial Networks (with Jonathon Hazell and Co-Pierre Georg

Journal of Economic Theory, 2021


Commitment and (In)Efficiency: a Bargaining Experiment (Supplementary Appendix) (with Marina Agranov)

Journal of the European Economic Association, 2021


A Network Approach to Public Goods (Supplementary Appendix) (with Ben Golub)

Journal of Political Economy, 2019


Decentralized Bargaining in Matching Markets: Efficient Stationary Equilibria and the Core  (with Francesco Nava)

Theoretical Economics, 2019


The role of Networks in Antitrust Investigations (with Andrea Galeotti)

Oxford Review of Economic Policy, 2019, Special issue on the economics of networks.


Networks and Economic Policy (with Sanjeev Goyal and Alex Teytelboym), 

Oxford Review of Economic Policy, 2019, Special issue on the economics of networks.


Inefficiencies in Networked Markets (Supplementary Appendix)

American Economic Journal: Microeconomics, 2015.

 

Financial Networks and Contagion (with Ben Golub and Matt Jackson)

American Economic Review, 2014.


How Sharing Information Can Garble Experts' Advice (with Ben Golub and Andrei Kirilenko,)

American Economic Review: Papers and Proceedings, 2014.


Book Chapters and Review Articles

Investment in Matching Markets (with Eduard Talamas, Draft Date: May 2021)

To appear in: Online and Matching-Based Market Design. Editors: Federico Echenique, Nicole Immorlica and Vijay V. Vazirani. Cambridge University Press.


Networks and Economics Fragility (joint with Ben Golub )

Annual Review of Economics, 2022 


Working Papers

Matching and Information Design in Marketplaces

(with Andrea Galeotti, Andrew Koh and Wenhao Li, Draft Date: February 2023)

There are many markets that are networked in these sense that not all consumers have access to (or are aware of) all products, while, at the same time, firms have some information about consumers and can distinguish some consumers from some others (for example, in online markets through cookies). With unit demand and price-setting firms we give a complete characterization of all welfare outcomes achievable in equilibrium (for arbitrary buyer-seller networks and arbitrary information structures), as well as the designs (networks and information structures) which implement them.


Corporate culture and organizational fragility

(with Ben Golub and Matt Leduc, Draft Date: January 2023)

Complex organizations accomplish tasks through many steps of collaboration among workers. Corporate culture supports collaborations by establishing norms and reducing misunderstandings. Because a strong corporate culture relies on costly, voluntary investments by many workers, we model it as an organizational public good, subject to standard free-riding problems, which become severe in large organizations. Our main finding is that voluntary contributions to culture can nevertheless be sustained, because an organization’s equilibrium productivity is endogenously highly sensitive to individual contributions. However, the completion of complex tasks is then necessarily fragile to small shocks that damage the organization’s culture.


Market Segmentation through Information (Supplementary Appendix)

(with Andrea Galeotti, Andrew Koh and Wenhao Li, Draft Date: November 2022)

Revision Requested by the Journal of Political Economy

A short video intended for a general interest (non-economist) audience is here.

Prodigious amounts of data are being collected by internet companies about their users’ preferences. We consider the information design problem of how to share this information with traditional companies which, in turn, compete on price by offering personalised discounts to customers. We provide a necessary and sufficient condition under which the internet company is able to perfectly segment and monopolise all such markets. This condition is surprisingly mild, and suggests room for regulatory oversight.


A capability approach to merger review

(with Iain Boa and David Foster, Draft date: October 2022)

Merger analysis typically focuses on possible strategic price effects in markets where there is existing competition between the merging firms. We refer to this as the product based approach. This paper proposes a complementary approach based on an assessment of the merging firms’ capabilities that can provide insights on potential merger effects, including in circumstances where the product based approach offers little practical guidance to antitrust authorities. Our approach is rooted in the resource-based view of business strategy that starts from the premise that it is a firm’s capabilities (sometimes called core competencies), which drive its competitive advantage across markets. We argue that mergers in which firms’ capabilities are less overlapping are more pro-competitive on several dimensions: immediate competition in overlapping markets, immediate competition in other markets, long-run competition and innovation.


Bargaining foundations for price taking in matching markets 

(with Eduard Talamas, Draft Date: November 2021)

In many markets, heterogenous agents make non-contractible investments before bargaining over both who matches with whom and the terms of trade. In static markets, the holdup problem—that is, inefficient investments caused by agents receiving only a fraction of their returns—is ubiquitous. Markets are often dynamic, however, with agents entering over time. Taking a general non-cooperative investment and bargaining approach, we show that the holdup problem vanishes in markets with dynamic entry as agents become patient: While there is substantial wiggle room for bargaining to determine outcomes, every bargaining outcome gives everyone her marginal product. 


Work in progress

Network Bottlenecks and Market Power (joint with Vasco Carvalho and John Spray)

Draft coming soon.


Globalizing Supply Networks: The impact on Innovation and Fragility (joint with Matt Jackson)

Draft coming soon.


Older Work

Ranking Agendas for Negotiations (with Ben Golub, Draft date: February 2015)

Consider a negotiation in which agents will make costly concessions to benefit others -- e.g., by implementing tariff reductions, environmental regulations or nuclear disarmament. An agenda specifies which issue or dimension agents will make concessions on; after an agenda is chosen, the negotiation comes down to the magnitude of each agent's contribution.  We seek a ranking of agendas based on the marginal costs and benefits they each generate at the status quo, which are captured in a Jacobian matrix. In a transferable utility (TU) setting, there is a simple ranking based on the best available social return per unit of cost (measured in the numeraire). When transfers are not available, the problem of ranking agendas is more difficult, and we take an axiomatic approach. First, we require the ranking not to depend on economically irrelevant changes of units. Second, we require that the ranking be consistent with the TU ranking on problems that are equivalent to TU problems in a suitable sense. The unique ranking satisfying these axioms is represented by the spectral radius (Frobenius root) of a matrix closely related to the Jacobian, whose entries measure the marginal benefits per unit marginal cost agents can confer on one another.


Heterogeneities and the Fragility of Labor Markets (Draft date: Nov 2015)

Workers' labor market participation decisions and firms' vacancy creation decisions are studied in a model where different matches generate different surpluses. An immediate consequence of these heterogeneities is that better matches are possible in thicker markets. This creates a thick market externality: when additional workers and firms enter the market, they confer net benefits on the other workers and firms by improving the expected quality of their matches. As a consequence, there is always too little entry by both workers and firms. The thick market externality has further implications. Quite generally labor markets will be fragile. Considering shocks to average match productivities, there will be a critical threshold at which a labor market suddenly collapses from supporting multiple workers and multiple firms in equilibrium to supporting no workers or firms in any equilibrium. All but one agent will suffer discontinuous losses as this threshold is passed and the market collapses.