nep-des New Economics Papers
on Economic Design
Issue of 2021‒02‒15
five papers chosen by
Alex Teytelboym
University of Oxford

  1. Choice Screen Auctions By Ostrovsky, Michael
  2. Strategy-proofness in experimental matching markets By Pablo Guillen; Róbert F. Veszteg
  3. Market sentiments and convergence dynamics in decentralized assignment economies By Bary Pradelski; Heinrich Nax
  4. Paying to Match: Decentralized Markets with Information Frictions By Marina Agranov; Ahrash Dianat; Larry Samuelson; Leeat Yariv
  5. Information Design by an Informed Designer By Frédéric Koessler; Vasiliki Skreta

  1. By: Ostrovsky, Michael (Stanford U)
    Abstract: Choice screen auctions have been recently deployed in 31 European countries, allowing consumers to choose their preferred search engine on Google's Android platform instead of being automatically defaulted to Google's own search engine. I show that a seemingly minor detail in the design of these auctions--whether they are conducted on a "per appearance" or a "per install" basis--plays a major role in the mix and characteristics of auction winners, and, consequently, in their expected overall market share. I also show that "per install" auctions distort the incentives of alternative search engines toward extracting as much revenue as possible from each user who installs them, at the expense of lowering the expected number of such users. The distortion becomes worse as the auction gets more competitive and the number of bidders in- creases. Empirical evidence from Android choice screen auctions conducted in 2020 is consistent with my theoretical results.
    Date: 2020–11
  2. By: Pablo Guillen (Faculty of Economics, The University of Sydney); Róbert F. Veszteg (School of Political Science and Economic, Waseda University)
    Abstract: We introduce two novel matching mechanisms, Reverse Top Trading Cycles (RTTC) and Reverse Deferred Acceptance (RDA), with the purpose of challenging the idea that the theoretical property of strategy-proofness induces high rates of truth-telling in economic experiments. RTTC and RDA are identical to the celebrated Top Trading Cycles (TTC) and Deferred Acceptance (DA) mechanisms, respectively, in all their theoretical properties except that their dominant-strategy equilibrium is to report one's preferences in the order opposite to the way they were induced. With the focal truthtelling strategy being out of equilibrium, we are able to perform a clear measurement of how much of the truth-telling reported for strategy-proof mechanisms is compatible with rational behavior and how much of it is caused by confused decision-makers following a default (very focal) strategy without understanding the structure of the game. In a school-allocation setting, we find that roughly half of the observed truth-telling under TTC and DA is the result of na¨ıve (non-strategic) behavior. Only 13-29% of participants' actions in RTTC and RDA are compatible with rational behavior. Further than that, by looking at the responses of those seemingly rational participants in control tasks, it becomes clear that even them lack a basic understanding of the game incentives. We argue that the use of a default option, confusion and other behavioral biases account for the vast majority of truthful play in both TTC and DA in laboratory experiments.
    Keywords: matching; strategy-proofness; truth-telling; focal point; rationality; laboratory experiment; school choice; revelation principle
    JEL: C78 D47 C91
    Date: 2019–08
  3. By: Bary Pradelski (POLARIS - Performance analysis and optimization of LARge Infrastructures and Systems - LIG - Laboratoire d'Informatique de Grenoble - UJF - Université Joseph Fourier - Grenoble 1 - UPMF - Université Pierre Mendès France - Grenoble 2 - CNRS - Centre National de la Recherche Scientifique - INPG - Institut National Polytechnique de Grenoble - Grenoble INP - Institut polytechnique de Grenoble - Grenoble Institute of Technology - Inria Grenoble - Rhône-Alpes - Inria - Institut National de Recherche en Informatique et en Automatique); Heinrich Nax
    Abstract: In two-sided markets with transferable utility ('assignment games'), we study the dynamics of trade arrangements and price adjustments as agents from the two market sides stochastically match, break up, and re-match in their pursuit of better opportunities. The underlying model of individual adjustments is based on the behavioral theories of adaptive learning and aspiration adjustment. Dynamics induced by this model converge to approximately optimal and stable market outcomes, but this convergence may be (exponentially) slow. We introduce the notion of a 'market sentiment' that governs which of the two market sides is temporarily more or less amenable to price adjustments, and show that such a feature may significantly speed up convergence.
    Keywords: market psychology,convergence time,matching markets,assignment games,core,evolutionary game theory
    Date: 2020–03
  4. By: Marina Agranov; Ahrash Dianat; Larry Samuelson; Leeat Yariv
    Abstract: We experimentally study decentralized one-to-one matching markets with transfers. We vary the information available to participants, complete or incomplete, and the surplus structure, supermodular or submodular. Several insights emerge. First, while markets often culminate in efficient matchings, stability is more elusive, reflecting the difficulty of arranging attendant transfers. Second, incomplete information and submodularity present hurdles to efficiency and especially stability; their combination drastically diminishes stability’s likelihood. Third, matchings form “from the top down” in complete-information supermodular markets, but exhibit many more and less-obviously ordered offers otherwise. Last, participants’ market positions matter far more than their dynamic bargaining styles for outcomes.
    Keywords: matching, incomplete information, stability, experiments
    Date: 2021
  5. By: Frédéric Koessler (PSE - Paris School of Economics - ENPC - École des Ponts ParisTech - ENS Paris - École normale supérieure - Paris - PSL - Université Paris sciences et lettres - UP1 - Université Panthéon-Sorbonne - CNRS - Centre National de la Recherche Scientifique - EHESS - École des hautes études en sciences sociales - INRAE - Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement, PJSE - Paris Jourdan Sciences Economiques - UP1 - Université Panthéon-Sorbonne - ENS Paris - École normale supérieure - Paris - PSL - Université Paris sciences et lettres - EHESS - École des hautes études en sciences sociales - ENPC - École des Ponts ParisTech - CNRS - Centre National de la Recherche Scientifique - INRAE - Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement); Vasiliki Skreta (CEPR - Center for Economic Policy Research - CEPR, University of Texas at Austin [Austin], UCL - University College of London [London])
    Abstract: A designer is privately informed about the state and chooses an information disclosure mechanism to influence the decisions of multiple agents playing a game. We define an intuitive class of incentive compatible information disclosure mechanisms which we coin interim optimal mechanisms. We prove that an interim optimal mechanism exists, and that it is an equilibrium outcome of the interim information design game. An ex-ante optimal mechanism may not be interim optimal, but it is whenever it is ex-post optimal. In addition, in leading settings in which action sets are binary, every ex-ante optimal mechanism is interim optimal. We relate interim optimal mechanisms to other solutions of informed principal problems.
    Keywords: strong-neologism proofness,neutral optimum,informed principal,Bayesian persuasion,interim information design,core mechanism,verifiable types.
    Date: 2021–02

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