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| Publications of Attila Ambrus :chronological alphabetical combined listing:%% Journal Articles @article{fds371291, Author = {Ambrus, A and Wayne, GAO and Milán, P}, Title = {Informal Risk Sharing with Local Information}, Journal = {Review of Economic Studies}, Volume = {89}, Number = {5}, Pages = {2329-2380}, Year = {2022}, Month = {October}, url = {http://dx.doi.org/10.1093/restud/rdab091}, Abstract = {This article considers the effect of contracting limitations in risk-sharing networks, arising for example from observability, verifiability, complexity, or cultural constraints. We derive necessary and sufficient conditions for Pareto efficiency under these constraints in a general setting, and we provide an explicit characterization of Pareto efficient bilateral transfer profiles under CARA utility and normally distributed endowments. Our model predicts that network centrality is positively correlated with consumption volatility, as more central agents become quasi-insurance providers to more peripheral agents. The proposed framework has important implications for the empirical specification of risk-sharing tests, allowing for local risk-sharing groups that overlap within the village network.}, Doi = {10.1093/restud/rdab091}, Key = {fds371291} } @article{fds359729, Author = {Ambrus, A and Baranovskyi, V and Kolb, A}, Title = {A Delegation-Based Theory of Expertise}, Journal = {American Economic Journal: Microeconomics}, Volume = {13}, Number = {4}, Pages = {373-419}, Publisher = {American Economic Association}, Year = {2021}, Month = {November}, Abstract = {We investigate information aggregation and competition in a delegation framework. An uninformed principal is unable to perform a task herself and must choose between one of two biased and imperfectly informed experts. In the focal equilibrium, experts exaggerate their biases, anticipating an ideological winner's curse. We show that having a second expert can benefit the principal, even when equally or more biased than the first expert. The principal can benefit from commitment to an "element of surprise" and prefers experts with equal rather than opposite biases.}, Key = {fds359729} } @article{fds326998, Author = {Ambrus, A and Kolb, A}, Title = {On defining ex ante payoffs in games with diffuse prior}, Journal = {Economic Theory}, Volume = {72}, Number = {2}, Pages = {445-472}, Year = {2021}, Month = {September}, url = {http://dx.doi.org/10.1007/s00199-020-01292-y}, Abstract = {While the diffuse prior has been widely used in applied economic theory for its technical convenience and as a way of modeling complete lack of knowledge, it is not formally defined, nor are ex ante payoffs in games under this prior. In this paper, we provide a formal treatment of the diffuse prior which can validate its application in games. We consider stationary games, in which players’ signals are translation invariant in the true state and players’ payoffs are translation invariant in actions together with the state. We show that strategies which admit well-defined expected payoffs under the diffuse prior are essentially stationary, being almost translation invariant in signals. Our analysis builds on two formal definitions. We define the diffuse prior through a limit construction, using sequences of well-defined priors that become increasingly dispersed. A class of strategy profiles is admissible if for any strategy profile, each player’s ex ante payoff along these sequences converges to a limit that does not depend on the particular sequence. A secondary contribution of the paper is an extension of the concept of distributional strategies (Milgrom and Weber in Math Oper Res 10:619–632, 1985) to a class of multistage games.}, Doi = {10.1007/s00199-020-01292-y}, Key = {fds326998} } @article{fds357650, Author = {Ambrus, A and Elliott, M}, Title = {Investments in social ties, risk sharing, and inequality}, Journal = {The Review of Economic Studies}, Volume = {88}, Number = {4}, Pages = {1624-1664}, Publisher = {Oxford University Press}, Year = {2021}, Month = {July}, Abstract = {This article investigates stable and efficient networks in the context of risk sharing, when it is costly to establish and maintain relationships that facilitate risk sharing. We find a novel trade-off between efficiency and equality: the most stable efficient networks also generate the most inequality. We then suppose that individuals can be split into groups, assuming that incomes across groups are less correlated than within a group but relationships across groups are more costly to form. The tension between efficiency and equality extends to these correlated income structures. More-central agents have stronger incentives to form across-group links, reaffirming the efficiency benefits of having highly central agents. Our results are robust to many extensions. In general, endogenously formed networks in the risk-sharing context tend to exhibit highly asymmetric structures, which can lead to stark inequalities in consumption levels.}, Key = {fds357650} } @article{fds352348, Author = {Ambrus, A and Field, E and Gonzalez, R}, Title = {Loss in the time of cholera: Long-run impact of a disease epidemic on the urban landscape}, Journal = {American Economic Review}, Volume = {110}, Number = {2}, Pages = {475-525}, Year = {2020}, Month = {January}, url = {http://dx.doi.org/10.1257/aer.20190759}, Abstract = {How do geographically concentrated income shocks influence the long-run spatial distribution of poverty within a city? We examine the impact on housing prices of a cholera epidemic in one neighborhood of nineteenth century London. Ten years after the epidemic, housing prices are significantly lower just inside the catchment area of the water pump that transmitted the disease. Moreover, differences in housing prices persist over the following 160 years. We make sense of these patterns by building a model of a rental market with frictions in which poor tenants exert a negative externality on their neighbors. This showcases how a locally concentrated income shock can persistently change the tenant composition of a block.}, Doi = {10.1257/aer.20190759}, Key = {fds352348} } @article{fds346383, Author = {Ambrus, A and Greiner, B}, Title = {Individual, Dictator, and Democratic punishment in public good games with perfect and imperfect observability}, Journal = {Journal of Public Economics}, Volume = {178}, Year = {2019}, Month = {October}, url = {http://dx.doi.org/10.1016/j.jpubeco.2019.104053}, Abstract = {In the context of repeated public good contribution games, we experimentally compare the institution of democratic punishment, where members of a group decide by majority voting whether to inflict punishment on another member, with individual peer-to-peer and dictatorial punishment institutions. Democratic punishment leads to more cooperation and higher average payoffs, both under perfect and imperfect monitoring of contributions. A comparison with dictatorial punishment suggests that the effect relative to traditional peer-to-peer punishment primarily works by curbing anti-social punishment and thereby establishing a closer connection between a member's contribution decision and whether subsequently being punished by others.}, Doi = {10.1016/j.jpubeco.2019.104053}, Key = {fds346383} } @article{fds343589, Author = {Ambrus, A and Greiner, B and Zednik, A}, Title = {The Effects of a ‘None of the Above’ Ballot Paper Option on Voting Behavior and Election Outcomes}, Journal = {Economic Research Initiatives at Duke (ERID) Working Paper}, Number = {277}, Year = {2019}, Month = {March}, Key = {fds343589} } @article{fds325427, Author = {Ambrus, A and Chaney, E and Salitskiy, I}, Title = {Pirates of the Mediterranean: An empirical investigation of bargaining with asymmetric information}, Journal = {Quantitative Economics}, Volume = {9}, Number = {1}, Pages = {217-246}, Publisher = {The Econometric Society}, Year = {2018}, Month = {March}, url = {http://dx.doi.org/10.3982/QE655}, Abstract = {We investigate the effect of delay on prices in bargaining situations using a data set containing thousands of captives ransomed from Barbary pirates between 1575 and 1692. Plausibly exogenous variation in the delay in ransoming provides evidence that negotiating delays decreased the size of ransom payments, and that much of the effect stems from the signalling value of strategic delay, in accordance with theoretical predictions. We also structurally estimate a version of the screening type bargaining model, adjusted to our context, and find that the model fits both the observed prices and acceptance probabilities well.}, Doi = {10.3982/QE655}, Key = {fds325427} } @article{fds318150, Author = {Ambrus, A and Calvano, E and Reisinger, M}, Title = {Either or Both Competition: A 'Two-Sided' Theory of Advertising with Overlapping Viewerships}, Journal = {American Economic Journal: Microeconomics}, Volume = {8}, Number = {3}, Pages = {189-222}, Publisher = {American Economic Association}, Year = {2016}, Month = {August}, url = {http://dx.doi.org/10.1257/mic.20150019}, Abstract = {In media markets, consumers spread their attention to several outlets, increasingly so as consumption migrates online. The traditional framework for competition among media outlets rules out this behavior by assumption. We propose a new model that allows consumers to choose multiple outlets and use it to study the effects on advertising levels and the impact of entry and mergers. We identify novel forces which reflect outlets' incentives to control the composition of their customer base. We link consumer preferences and advertising technologies to market outcomes. The model can explain several empirical regularities that are difficult to reconcile with existing models.}, Doi = {10.1257/mic.20150019}, Key = {fds318150} } @article{fds320205, Author = {Ambrus, A and Egorov, G}, Title = {Delegation and Nonmonetary Incentives}, Journal = {Economic Research Initiatives at Duke (ERID)}, Volume = {171}, Number = {200}, Pages = {49 pages}, Publisher = {Elsevier BV}, Year = {2015}, Month = {December}, url = {http://dx.doi.org/10.1016/j.jet.2017.06.002}, Abstract = {In many contracting settings, actions costly to one party but with no direct benefits to the other (money-burning) may be part of the explicit or implicit contract. A leading example is bureaucratic procedures in an employer-employee relationship. We study a model of delegation with an informed agent, where the principal may impose money-burning on the agent as a function of the agent’s choice of action, and show that money-burning may be part of the optimal contract. This result holds even if action-contingent monetary transfers are possible, as long as transfers from the principal to the agent are bounded from below (as in limited liability or minimal wage requirements). In fact, the optimal contract can involve a combination of both efficient monetary incentives and inefficient nonmonetary incentives through money burning. Our model delivers some results novel to the delegation literature. First, money-burning is more likely if the principal is more sensitive to the choice of action than the agent. This is consistent with the perception that there is more bureaucratization in large organizations. Second, money-burning is more likely if the agent’s limited liability constraint is tighter relative to his participation constraint. This implies that a higher minimum wage distorts employment contracts towards using socially wasteful nonmonetary incentives, leading to a Pareto inferior outcome as the agent is still held down to his reservation value through increased money burning.}, Doi = {10.1016/j.jet.2017.06.002}, Key = {fds320205} } @article{fds320206, Author = {Ambrus, A and Egorov, G}, Title = {Supplementary Appendix to 'Delegation and Nonmonetary Incentives'}, Journal = {Economic Research Initiatives at Duke (ERID)}, Number = {201}, Pages = {21 pages}, Year = {2015}, Month = {December}, Abstract = {Supplementary Appendix to "Delegation and Nonmonetary Incentives."}, Key = {fds320206} } @article{fds320207, Author = {Ambrus, A and Greiner, B and Sastro, A}, Title = {The Case for Nil Votes: Voter Behavior Under Asymmetric Information in Compulsory and Voluntary Voting Systems}, Journal = {Economic Research Initiatives at Duke (ERID)}, Volume = {154}, Number = {199}, Pages = {66 pages}, Publisher = {Elsevier BV}, Year = {2015}, Month = {December}, url = {http://dx.doi.org/10.1016/j.jpubeco.2017.08.006}, Abstract = {We experimentally study the impact of adding an explicit nil vote option to the ballot in both compulsory and voluntary voting settings. We investigate this issue in an informational voting setting, in which some voters are uninformed and face the swing voter’s curse, implying that they can only affect the expected election outcome adversely. We generate predictions using a simple model of strategic voting in which some voters receive a psychological benefit (along the lines of Riker and Ordeshook (1968)) from choosing an action that they consider a legitimate participation in the election. We test our model in a double-blind pen-and-paper laboratory experiment, and find that the main comparative predictions of the model hold in the data, particularly strongly for compulsory voting. In particular, both under compulsory and voluntary voting, introducing a nil vote option reduces the number of uninformed voters casting a vote for a candidate, increasing voters’ expected welfare. Additionally, it eradicates strategic invalid votes under compulsory voting.}, Doi = {10.1016/j.jpubeco.2017.08.006}, Key = {fds320207} } @article{fds320208, Author = {Ambrus, A and Baranovskyi, V and Kolb, A}, Title = {A Delegation-Based Theory of Expertise}, Journal = {Economic Research Initiatives at Duke (ERID)}, Number = {193}, Pages = {45 pages}, Year = {2015}, Month = {September}, Abstract = {We investigate competition in a delegation framework, with a coarsely informed principal. Two imperfectly informed and biased experts simultaneously propose action choices. A principal with a diffuse prior, and only being able to ordinally compare the two proposals, has to choose one of them. The selected expert might receive a bonus payment. We show that having a second expert benefits the principal, even if the two experts have the same biases and the bonus of the winner is zero. In contrast with other models of expertise, in our setting the principal prefers experts with equal rather than opposite biases. Increasing the bonus brings experts closer to truthful reporting, but this only benefits the principal up to a threshold level, with further increases in the bonus strictly decreasing her payoffs. A methodological contribution of our paper is characterizing restrictions on the set of strategies which allows a formal generalization of ex ante expected payoffs to games with diffuse prior.}, Key = {fds320208} } @article{fds320209, Author = {Ambrus, A and Baranovskyi, V and Kolb, A}, Title = {Supplementary Appendix to 'A Delegation-Based Theory of Expertise'}, Journal = {Economic Research Initiatives at Duke (ERID)}, Number = {194}, Pages = {16 pages}, Year = {2015}, Month = {September}, Abstract = {This supplement provides welfare results not contained in the main text and a proof of Lemma A.1. For small bonuses, a mixed equilibrium exists if and only if a downward equilibrium exists; if so, it is unique. For large bonuses, we find a unique candidate for mixed equilibrium and show that mixed and upward equilibria cannot co-exist. Also, we give an example for equal biases, where this candidate is indeed a mixed equilibrium. However, when biases are different enough and the bonus is high, a mixed equilibrium does not exist. Though a general analytical comparison is infeasible, we show that mixed equilibria are inferior to upward equilibrium or simple delegation in various special cases.}, Key = {fds320209} } @article{fds320210, Author = {Ambrus, A and Greiner, B}, Title = {Democratic Punishment in Public Good Games with Perfect and Imperfect Observability}, Journal = {Economic Research Initiatives at Duke (ERID)}, Number = {183}, Pages = {27 pages}, Year = {2015}, Month = {August}, Abstract = {In the context of repeated public good contribution games, we experimentally investigate the impact of democratic punishment, when members of a group decide by majority voting whether to inflict punishment on another member, relative to individual peer-to-peer punishment. Democratic punishment leads to more cooperation and higher average payoffs, both under perfect and imperfect monitoring of contributions, primarily by curbing anti-social punishment and thereby establishing a closer connection between a member’s contribution decision and whether subsequently being punished by others. We also find that participating in a democratic punishment procedure makes even non-contributors’ punishment intentions more pro-social.}, Key = {fds320210} } @article{fds320211, Author = {Ambrus, A and Ishii, Y}, Title = {On Asynchronicity of Moves and Coordination}, Journal = {Economic Research Initiatives at Duke (ERID)}, Number = {185}, Pages = {47 pages}, Year = {2015}, Month = {March}, Abstract = {This paper shows that asynchronicity of moves can lead to a unique prediction in coordination games, in an infinite-horizon setting, under certain conditions on off-equilibrium payoffs. In two-player games we derive necessary and sufficient conditions for play ultimately being absorbed in the Pareto dominant Nash equilibrium of the stage game, for every Markov perfect equilibrium. For players patient enough, the condition is that the Pareto dominant Nash equilibrium is also risk dominant, but for lower levels of patience the condition departs from simple risk-dominance. For general n-player symmetric games with patient players, we show that a necessary and sufficient condition for the Pareto dominant Nash equilibrium to be the unique limit outcome in all symmetric Markov perfect equilibrium is a particular generalization of risk-dominance for more than two players. We provide extensions to the unique selection results to all subgame perfect Nash equilibria, and to coordination games in which different players prefer different Nash equilibria of the stage game.}, Key = {fds320211} } @article{fds325425, Author = {Ambrus, A and Chandrasekhar, AG and Elliott, M}, Title = {Social Investments, Informal Risk Sharing, and Inequality}, Journal = {Economic Research Initiatives at Duke (ERID) Working Paper}, Number = {179}, Year = {2015}, Month = {March}, Key = {fds325425} } @article{fds320214, Author = {Ambrus, A and Ásgeirsdóttir, T and Noor, J and Sandor, L}, Title = {Compensated Discount Functions: An Experiment on the Influence of Expected Income on Time Preferences}, Journal = {Economic Research Initiatives at Duke (ERID)}, Number = {168}, Pages = {43 pages}, Year = {2015}, Month = {March}, Key = {fds320214} } @article{fds320213, Author = {Ambrus, A and Asgeirsdottir, TL and Noor, J and Sándor, L}, Title = {Supplement to 'Compensated Discount Functions: An Experiment on the Influence of Expected Income on Time Preferences'}, Journal = {Economic Research Initiatives at Duke (ERID) Working Paper}, Number = {169}, Year = {2015}, Month = {March}, Abstract = {This Supplementary Appendix contains the English translations of the experimental questionnaire, survey questions, and instructions that were used in our experimental sessions on June 9th and 10th of 2010. For the original Icelandic language documents, please contact the authors. The paper 'Compensated Discount Functions - An Experiment on Integrating Rewards with Expected Income' to which this Supplement applies is available at the following URL: <a href=http://ssrn.com/abstract=2446602>http://ssrn.com/abstract=2446602</a>}, Key = {fds320213} } @article{fds325426, Author = {Ambrus, A and En Lu and SE}, Title = {A continuous-time model of multilateral bargaining}, Journal = {American Economic Journal: Microeconomics}, Volume = {7}, Number = {1}, Pages = {208-249}, Publisher = {American Economic Association}, Year = {2015}, Month = {January}, url = {http://dx.doi.org/10.1257/mic.20100029}, Abstract = {We propose a finite-horizon continuous-time framework for coalitional bargaining, in which players can make offers at random discrete times. In our model: (i) expected payoffs in Markov perfect equilibrium (MPE) are unique, generating sharp predictions and facilitating comparative statics; and (ii) MPE are the only subgame perfect Nash equilibria (SPNE) that can be approximated by SPNE of nearby discrete-time bargaining models. We investigate the limit MPE payoffs as the time horizon goes to infinity and players get infinitely patient. In convex games, we establish that the set of these limit payoffs achievable by varying recognition rates is exactly the core of the characteristic function.}, Doi = {10.1257/mic.20100029}, Key = {fds325426} } @article{fds237850, Author = {Ambrus, A and Lu, SE}, Title = {Almost fully revealing cheap talk with imperfectly informed senders}, Journal = {Games and Economic Behavior}, Volume = {88}, Pages = {174-189}, Publisher = {Elsevier BV}, Year = {2014}, Month = {November}, ISSN = {0899-8256}, url = {http://dx.doi.org/10.1016/j.geb.2014.09.001}, Abstract = {We show that in multi-sender communication games where senders imperfectly observe the state, if the state space is large enough, then there can exist equilibria arbitrarily close to full revelation of the state as the noise in the senders' observations gets small. In the case of replacement noise, where the senders observe the true state with high probability, we show this under mild assumptions, for both unbounded and large bounded state spaces. In the case of continuous noise, where senders observe a signal distributed continuously over a small interval around the true state, we establish this for unbounded state spaces. The results imply that when there are multiple experts from whom to solicit information, if the state space is large, then even when the state is observed imperfectly, there are communication equilibria that are strictly better for the principal than delegating the decision right to one of the experts.}, Doi = {10.1016/j.geb.2014.09.001}, Key = {fds237850} } @article{fds325428, Author = {Ambrus, A and Mobius, M and Szeidl, A}, Title = {Consumption Risk-Sharing in Social Networks}, Journal = {American Economic Review}, Volume = {104}, Number = {1}, Year = {2014}, Month = {January}, Abstract = {We develop a model in which connections between individuals serve as social collateral to enforce informal insurance payments. We show that: (i) The degree of insurance is governed by the expansiveness of the network, measured with the per capita number of connections that groups have with the rest of the community. "Two-dimensional" networks?like real-world networks in Peruvian villages?are sufficiently expansive to allow very good risk-sharing. (ii) In second- best arrangements, insurance is local: agents fully share shocks within, but imperfectly between endogenously emerging risk-sharing groups. We also discuss how endogenous social collateral affects our results.}, Key = {fds325428} } @article{fds320215, Author = {Ambrus, A and Greiner, B and Pathak, P}, Title = {How Individual Preferences Get Aggregated in Groups - An Experimental Study}, Journal = {Economic Research Initiatives at Duke (ERID)}, Number = {158}, Pages = {37 pages}, Year = {2013}, Month = {September}, Abstract = {This paper experimentally investigates how individual preferences, through unrestricted deliberation, get aggregated into a group decision in two contexts: reciprocating gifts, and choosing between lotteries. In both contexts we find that median group members have a significant impact on the group decision, but particular other members also have some influence. Non-median members closer to the median tend to have more influence than other members. By investigating the same individual’s influence in different groups, we find evidence for relative position in the group having a direct effect on influence. We do not find evidence that group choice exhibits a shift in a particular direction that is independent of member preferences and caused by the group decision context itself. We also find that group deliberation not only involves bargaining and compromise, but it also involves persuasion: preferences tend to shift towards the choice of the individual’s previous group, especially for those with extreme individual preferences.}, Key = {fds320215} } @article{fds320216, Author = {Ambrus, A and Ishii, Y and Burns, J}, Title = {Gradual Bidding in Ebay-Like Auctions}, Journal = {Economic Research Initiatives at Duke (ERID)}, Number = {129}, Pages = {59 pages}, Year = {2013}, Month = {September}, Abstract = {This paper shows that in online auctions like eBay, if bidders can only place bids at random times, then many di fferent equilibria arise besides truthful bidding, despite the option to leave proxy bids. These equilibria can involve gradual bidding, periods of inactivity, and waiting to start bidding towards the end of the auction - bidding behaviors common on eBay. Bidders in such equilibria implicitly collude to keep the increase of the winning price slow over the duration of the auction. In a common value environment, we characterize a class of equilibria that include the one in which bidding at any price is maximally delayed, and all bids minimally increment the price. The seller's revenue can be a small fraction of what could be obtained at a sealed-bid second-price auction, and in the worst equilibrium it is decreasing in the value of the object. With many bidders, we show that this equilibrium has the feature that bidders are passive until near the end of the auction, and then they start bidding incrementally.}, Key = {fds320216} } @article{fds237851, Author = {Ambrus, A and Egorov, G}, Title = {Comment on "Commitment vs. Flexibility"}, Journal = {Econometrica}, Volume = {81}, Number = {5}, Pages = {2113-2124}, Publisher = {The Econometric Society}, Year = {2013}, Month = {January}, ISSN = {0012-9682}, url = {http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000325084100012&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=47d3190e77e5a3a53558812f597b0b92}, Abstract = {This comment corrects two results in the 2006 Econometrica paper by Amador, Werning, and Angeletos (AWA), that features a model in which individuals face a trade-off between flexibility and commitment. First, in contrast to Proposition 1 in AWA, we show that money-burning can be part of the ex ante optimal contract when there are two states. Second, in contrast to Proposition 2 in AWA, we show that money-burning can be imposed at the top (in the highest liquidity shock state), even when there is a continuum of states. We provide corrected versions of the above results. © 2013 The Econometric Society.}, Doi = {10.3982/ECTA10739}, Key = {fds237851} } @article{fds237852, Author = {Ambrus, A and Azevedo, EM and Kamada, Y and Takagi, Y}, Title = {Legislative Committees as Information Intermediaries}, Journal = {Journal of Economic Behavior and Organization}, Volume = {94}, Pages = {103-115}, Publisher = {Elsevier BV}, Year = {2013}, ISSN = {0167-2681}, url = {http://dx.doi.org/10.1016/j.jebo.2013.08.003}, Abstract = {This paper considers a model of legislative decision-making, in which information must be collected from a strategic lobbyist. The legislature appoints a committee to communicate with the lobbyist and propose a bill, and determines whether the proposal is processed under open or closed rule. Consistent with empirical evidence, it can be optimal for the legislature to appoint a biased committee and, depending on the lobbyist's bias, both open and closed rule are used in equilibrium. For small lobbyist bias, it is optimal to choose closed rule and a committee whose interests are perfectly aligned with the lobbyist's. For intermediate lobbyist bias, closed rule remains optimal with a committee whose preferences lie between those of the legislature and those of the lobbyist. For large lobbyist bias, open rule and a committee biased against the lobbyist become optimal. © 2013 Elsevier B.V.}, Doi = {10.1016/j.jebo.2013.08.003}, Key = {fds237852} } @article{fds237855, Author = {Ambrus, A and Greiner, B}, Title = {Imperfect public monitoring with costly punishment: An experimental study}, Journal = {American Economic Review}, Volume = {102}, Number = {7}, Pages = {3317-3332}, Publisher = {American Economic Association}, Year = {2012}, Month = {December}, ISSN = {0002-8282}, url = {http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000312093000007&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=47d3190e77e5a3a53558812f597b0b92}, Abstract = {This paper experimentally investigates the effects of a costly punishment option on cooperation and social welfare in long, finitely repeated public good contribution games. In a perfect monitoring environment, increasing the severity of the potential punishment monotonically increases average net payoffs. In a more realistic imperfect monitoring environment, we find a U-shaped relationship. Access to a standard punishment technology in this setting significantly decreases net payoffs, even in the long run. Access to a severe punishment technology leads to roughly the same payoffs as with no punishment option, as the benefits of increased cooperation offset the social costs of punishing. Copyright © 2012 by the American Economic Association.}, Doi = {10.1257/aer.102.7.3317}, Key = {fds237855} } @article{fds320218, Author = {Ambrus, A and Sandor, L and You, H}, Title = {Testing an Informational Theory of Legislation: Evidence from the U.S. House of Representatives: Supplementary Appendix}, Journal = {Economic Research Initiatives at Duke (ERID)}, Number = {122}, Pages = {13 pages}, Year = {2012}, Month = {October}, Abstract = {Supplementary Appendix to Testing an Informational Theory of Legislation: Evidence from the U.S. House of Representatives.}, Key = {fds320218} } @article{fds320219, Author = {Ambrus, A and Rozen, K}, Title = {Rationalizing Choice with Multi-Self Models}, Journal = {Economic Research Initiatives at Duke (ERID)}, Volume = {125}, Number = {128}, Pages = {42 pages}, Year = {2012}, Month = {May}, Abstract = {This paper studies a class of multi-self decision-making models proposed in economics, psychology, and marketing. In this class, choices arise from the set-dependent aggregation of a collection of utility functions, where the aggregation procedure satisfies some simple properties. We propose a method for characterizing the extent of irrationality in a choice behavior, and use this measure to provide a lower bound on the set of choice behaviors that can be rationalized with n utility functions. Under an additional assumption (scale-invariance), we show that generically at most five "reasons" are needed for every "mistake."}, Key = {fds320219} } @article{fds320220, Author = {Ambrus, A and Egorov, G}, Title = {Commitment-Flexibility Trade-Off and Withdrawal Penalties}, Journal = {Economic Research Initiatives at Duke (ERID)}, Number = {130}, Pages = {29 pages}, Year = {2012}, Month = {March}, Abstract = {Withdrawal penalties are common features of time deposit contracts offered by commercial banks, as well as individual retirement accounts and employer-sponsored plans. Moreover, there is a significant amount of early withdrawals from these accounts, despite the associated penalties, and empirical evidence shows that liquidity shocks of depositors are a major driving force of this. Using the consumption-savings model proposed by Amador, Werning and Angeletos in their 2006 Econometrica paper (henceforth AWA), in which individuals face the trade-off between flexibility and commitment, we show that withdrawal penalties can be part of the optimal contract, despite involving money-burning from an ex ante perspective. For the case of two states (which we interpret as “normal times” and a “negative liquidity shock”), we provide a full characterization of the optimal contract, and show that within the parameter region where the first best is unattainable, the likelihood that withdrawal penalties are part of the optimal contract is decreasing in the probability of a negative liquidity shock, increasing in the severity of the shock, and it is nonmonotonic in the magnitude of present bias. We also show that contracts with the same qualitative feature (withdrawal penalties for high types) arise in continuous state spaces, too. Our conclusions differ from AWA because the analysis in the latter implicitly assumes that the optimal contract is interior (the amount withdrawn from the savings account is strictly positive in each period in every state). We show that for any utility function consistent with their framework there is an open set of parameter values for which the optimal contract is a corner solution, inducing money burning in some states.}, Key = {fds320220} } @article{fds325429, Author = {Ambrus, A and Chaney, EJ and Salitskiy, I}, Title = {Appendix for Pirates of the Mediterranean: An Empirical Investigation of Bargaining with Transaction Costs}, Journal = {Economic Research Initiatives at Duke (ERID) Working Paper}, Number = {116}, Year = {2011}, Month = {December}, Key = {fds325429} } @article{fds237854, Author = {Ambrus, A and Azevedo, E and Kamada, Y}, Title = {Hierarchical cheap talk}, Journal = {Accepted by Theoretical Economics}, Volume = {8}, Number = {1}, Pages = {233-261}, Publisher = {The Econometric Society}, Year = {2011}, url = {http://public.econ.duke.edu/~aa231/hierarch_final04.pdf}, Abstract = {We investigate situations in which agents can communicate to each other only through a chain of intermediators, for example, because they have to obey institutionalized communication protocols. We assume that all involved in the communication are strategic and might want to influence the action taken by the final receiver. The set of pure strategy equilibrium outcomes is simple to characterize, is monotonic in each intermediator's bias, and does not depend on the order of intermediators; intermediation in these equilibria cannot improve information transmission. However, none of these conclusions holds for mixed equilibria. We provide a partial characterization of mixed equilibria, and offer an economically relevant sufficient condition for every equilibrium to be outcome-equivalent to a pure equilibrium and hence for the simple characterization and comparative statics results to hold for the set of all equilibria. © 2013 Attila Ambrus, Eduardo M. Azevedo, and Yuichiro Kamada.}, Doi = {10.3982/TE1038}, Key = {fds237854} } @article{fds237856, Author = {Ambrus, A and Pathak, P}, Title = {Cooperation over finite horizons: a theory and experiments}, Journal = {Journal of Public Economics}, Volume = {95}, Number = {1-2}, Pages = {500-512}, Publisher = {Elsevier BV}, Year = {2011}, url = {http://public.econ.duke.edu/~aa231/public_good090510_ALL.pdf}, Abstract = {This paper shows that the presence of different types of players - those who only care about their own material payoffs and those who reciprocate others' contributions - can explain the robust features of observed contribution patterns in public good contribution games, even without the presence of asymmetric information. We show what conditions on reciprocity are sufficient for a unique perfect equilibrium, in which contributions are decreasing. Under these conditions, selfish players have enough future benefits to induce subsequent contributions by reciprocal players, and this incentive diminishes as the end of the game approaches. The model explains the puzzling restart effect and is consistent with various other empirical findings. We also report the results of a series of experiments, using a probabilistic continuation design in which after each set of 10-period games, the group is restarted with low probability. We find specific support for the theory in our data, including that selfish players (identified exogenously) stop contributing earlier than reciprocal players, as directly implied by the model. © 2010 Elsevier B.V.}, Doi = {10.1016/j.jpubeco.2010.11.016}, Key = {fds237856} } @article{fds237857, Author = {Ambrus, A and Field, E and Torero, M}, Title = {Muslim family law, prenuptial agreements, and the emergence of dowry in Bangladesh}, Journal = {Quarterly Journal of Economics}, Volume = {125}, Number = {3}, Pages = {1349-1397}, Publisher = {Oxford University Press (OUP)}, Year = {2010}, Month = {August}, ISSN = {0033-5533}, url = {http://dx.doi.org/10.1162/qjec.2010.125.3.1349}, Abstract = {We explain trends in dowry levels in Bangladesh by drawing attention to an institutional feature of marriage contracts previously ignored in the literature: mehr or traditional Islamic bride-price. We develop a model of marriage contracts in which mehr serves as a barrier to husbands exiting marriage and a component of dowry as an amount that ex ante compensates the groom for the cost of mehr. We investigate how mehr and dowry respond to exogenous changes in the costs of polygamy and divorce, and show that our model gives a different set of predictions than traditional models. We show that major changes in dowry levels took place precisely after the legal changes, corresponding to simultaneous changes in levels of mehr. © 2010 by the President and Fellows of Harvard College and the Massachusetts Institute of Technology.}, Doi = {10.1162/qjec.2010.125.3.1349}, Key = {fds237857} } @article{fds237861, Author = {Ambrus, A}, Title = {Theories of coalitional rationality}, Journal = {Journal of Economic Theory}, Volume = {144}, Number = {2}, Pages = {676-695}, Publisher = {Elsevier BV}, Year = {2009}, Month = {March}, ISSN = {0022-0531}, url = {http://dx.doi.org/10.1016/j.jet.2007.03.010}, Abstract = {This paper generalizes the concept of best response to coalitions of players and offers epistemic definitions of coalitional rationalizability in normal form games. The (best) response of a coalition is defined to be an operator from sets of conjectures to sets of strategies. A strategy is epistemic coalitionally rationalizable if it is consistent with rationality and common certainty that every coalition is rational. A characterization of this solution set is provided for operators satisfying four basic properties. Special attention is devoted to an operator that leads to a solution concept that is generically equivalent to the iteratively defined concept of coalitional rationalizability. © 2008 Elsevier Inc. All rights reserved.}, Doi = {10.1016/j.jet.2007.03.010}, Key = {fds237861} } @article{fds237860, Author = {Ambrus, A and Argenziano, R}, Title = {Asymmetric networks in two-sided markets}, Journal = {American Economic Journal: Microeconomics}, Volume = {1}, Number = {1}, Pages = {17-52}, Publisher = {American Economic Association}, Year = {2009}, Month = {February}, ISSN = {1945-7669}, url = {http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000284507300002&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=47d3190e77e5a3a53558812f597b0b92}, Abstract = {This paper investigates pricing decisions and network choices in twosided markets with network externalities. Consumers are heterogeneous in how much they value the externality. Imposing restrictions on the extent of coordination failure among consumers generates clear qualitative conclusions about equilibrium market configurations. Multiple asymmetric networks can coexist in equilibrium, both in the case of a monopolist network provider and in the case of competing providers. These equilibria have the property that one network is cheaper and larger on one side, while the other network is cheaper and larger on the other side. Product differentiation is endogenized by consumers' network choices.}, Doi = {10.1257/mic.1.1.17}, Key = {fds237860} } @article{fds237858, Author = {Ambrus, A and Weinstein, J}, Title = {Price dispersion and loss leaders}, Journal = {Theoretical Economics}, Volume = {3}, Number = {4}, Pages = {525-537}, Year = {2008}, Month = {December}, ISSN = {1555-7561}, Abstract = {Dispersion in retail prices of identical goods is inconsistent with the standard model of price competition among identical firms, which predicts that all prices will be driven down to cost. One common explanation for such dispersion is the use of a loss-leader strategy, in which a firm prices one good below cost in order to attract a higher customer volume for profitable goods. By assuming each consumer is forced to buy all desired goods at a single firm, we create the possibility of an effective loss-leader strategy. We find that such a strategy cannot occur in equilibrium if individual demands are inelastic, or if demands are diversely distributed. We further show that equilibrium loss leaders can occur (and can result in positive profits) if there are demand complementarities, but only with delicate relationships among the preferences of all consumers. Copyright © 2008 Attila Ambrus and Jonathan Weinstein.}, Key = {fds237858} } @article{fds237859, Author = {Field, E and Ambrus, A}, Title = {Early marriage, age of menarche, and female schooling attainment in Bangladesh}, Journal = {Journal of Political Economy}, Volume = {116}, Number = {5}, Pages = {881-891}, Publisher = {University of Chicago Press}, Year = {2008}, Month = {October}, ISSN = {0022-3808}, url = {http://dx.doi.org/10.1086/593333}, Abstract = {Using data from rural Bangladesh, we explore the hypothesis that women attain less schooling as a result of social and financial pressure to marry young. We isolate the causal effect of marriage timing using age of menarche as an instrumental variable. Our results indicate that each additional year that marriage is delayed is associated with 0.22 additional year of schooling and 5.6 percent higher literacy. Delayed marriage is also associated with an increase in use of preventive health services. In the context of competitive marriage markets, we use the above results to obtain estimates of the change in equilibrium female education that would arise from introducing age of consent laws. © 2008 by The University of Chicago. All rights reserved.}, Doi = {10.1086/593333}, Key = {fds237859} } @article{fds237862, Author = {Ambrus, A and Takahashi, S}, Title = {Multi-sender cheap talk with restricted state spaces}, Journal = {Theoretical Economics}, Volume = {3}, Number = {1}, Pages = {1-27}, Year = {2008}, Month = {March}, ISSN = {1555-7561}, Abstract = {This paper analyzes multi-sender cheap talk when the state space might be restricted, either because the policy space is restricted or the set of rationalizable policies of the receiver is not the whole space. We provide a necessary and sufficient condition for the existence of a fully-revealing perfect Bayesian equilibrium for any state space. We show that if biases are large enough and are not in similar directions, where the notion of similarity depends on the shape of the state space, then there is no fully-revealing perfect Bayesian equilibrium. The results suggest that boundedness, as opposed to dimensionality, of the state space plays an important role in determining the qualitative implications of a cheap talk model. We also investigate equilibria that satisfy a robustness property diagonal continuity. Copyright © 2008 Attila Ambrus and Satoru Takahashi.}, Key = {fds237862} } @article{fds237863, Author = {Ambrus, A}, Title = {Coalitional rationalizability}, Journal = {Quarterly Journal of Economics}, Volume = {121}, Number = {3}, Pages = {903-929}, Publisher = {Oxford University Press (OUP)}, Year = {2006}, Month = {August}, ISSN = {0033-5533}, url = {http://dx.doi.org/10.1162/qjec.121.3.903}, Abstract = {This paper investigates how groups or coalitions of players can act in their collective interest in noncooperative normal form games even if equilibrium play is not assumed. The main idea is that each member of a coalition will confine play to a subset of their strategies if it is in their mutual interest to do so. An iterative procedure of restrictions is used to define a noncooperative solution concept, the set of coalitionally rationalizable strategies. The procedure is analogous to iterative deletion of never best response strategies, but operates on implicit agreements by different coalitions. The solution set is a nonempty subset of the rationalizable strategies. © 2006 by the President and Fellows of Harvard College and the Massachusetts Institute of Technology.}, Doi = {10.1162/qjec.121.3.903}, Key = {fds237863} } | |
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