Binomial menu auctions in government formation

In a menu auction, players submit bids for all choices the auctioneer A can make, and A then makes the choice that maximizes the sum of bids. In a binomial menu auction (BMA), players submit acceptance sets (indicating which choices they would support), and A chooses the option that maximizes his utility subject to acceptance of the respective players. Monetary transfers may be implicit, but players may also bid by offering "favors" and the like. BMAs provide a unified representation of both monetary and non-monetary bidding, which I apply to model government formation. First, I analyze general BMAs, characterize the solution under complete information and establish outcome uniqueness (for both, sealed bid and Dutch formats). Second, in case monetary transfers are possible, BMAs are shown to implement VCG mechanisms. Finally, in case transfers are impossible, BMAs extend the model of proto-coalition bargaining and are specifically applied to government formation.menu auction; demand commitment; proto-coalition bargaining; VCG mechanism

Hierarchical Reasoning versus Iterated Reasoning in p-Beauty Contest Guessing Games

This paper analyzes strategic choice in p-beauty contests. We first show that it is not generally a best reply to guess the expected target value (accounting for the own weight) even in games with n>2 players and that iterated best response sequences are not unique even after perfect/cautious refinement. This implies that standard formulations of ``level-k'' models are neither exactly nor uniquely rationalizable by belief systems based on iterated best response. Second, exact modeling of iterated reasoning weakens the fit considerably and reveals that equilibrium types dominate the populations. We also show that ``levels of reasoning'' cannot be measured regardless of the underlying model. Third, we consider a ``nested logit'' model where players choose their level. It dispenses with belief systems between players and is rationalized by a random utility model. Besides being internally consistent, nested logit equilibrium fits better than three variants of the level-k model in standard data sets.logit equilibrium, hierarchical response, level-k, beauty contest

A Theory of coalition Bargaining

When voting takes place in democratic institutions, we find (either explicitly or implicitly) that there is an agenda setter or a formateur. Such players are uniquely able to make substantive proposals for given topics. Their statuses remain intact even after rejection of proposals, but they must revise rejected proposals constructively (e.g. towards a compromise). We model this in a general environment, show that the equilibrium outcome is generically unique, and characterize it explicitely. The equilibrium outcome is robust to (partially) binding communication between the formateur and the voters. As illustrations, we consider majority bargaining about a cake (leaned on Baron and Ferejohn,1989),where the formateur ends up being a perfect dictator, and a model of legislative voting (leaned on Jackson and Moselle,2002), where he is a dictator if his ideological position is within the quartiles of the parliament. In these cases, our model implements (reversed) McKelvey majority path. Depending on the valuations, the formateur´s power may be weakened when parliamentary decisions can be revised, as this may faciliate tacit collusion amongst the voters. --coalitional bargaining,legislature,non-cooperative

Proto-coalition bargaining and the core

In the proto-coalition model of government formation, formateur F appoints a proto-coalition and asks its members whether to start negotiating a coalition contract. If all accept, then the proto-coalition forms and starts negotiating; otherwise a caretaker government assumes office. I extend this model by allowing F to revise the chosen proto-coalition after rejections, that he states pre-conditions for the subsequent negotiations, and that F's opponents may publicly pre-commit to accept/reject certain proposals. The set of equilibrium outcomes is identified as the core if F's opponents can pre-commit and as the convex hull of the core if they cannot pre-commit credibly. This extended model eliminates two flaws of the standard model: it explains why F cannot always install his favored coalition (whatever the status quo) and why "important" coalition members may have more bargaining power in the subsequent negotiations than others.coalition formation, non-cooperative bargaining, core

Are gas release auctions effective?

European and national cartel authorities have required dominant national gas pipelines to auction off certain quantities (typically about 10 % of their sales) to competitors. Do such auctions really improve the competitiveness of the wholesale market? Based on a model where oligopolistic pipelines could voluntarily auction gas to competitors (or precommit on certain sales otherwise) we conclude that such release auctions often have no effect because the additional obligations will simply crowd out voluntary sales. --

On the Allocative Efficiency of Ownership Unbundling

We analyze vertical structures where a regulated network operator serves n network users, and the network users compete in quantities for customers. We distinguish two cases: (i) none of the network users are related to the network operator (ownership unbundling), (ii) one of the network users is partially integrated with the operator and the others are disintegrated (legal unbundling). We seek to understand when ownership unbundling leads to lower customer prices, and formalize necessary conditions. In general, legal unbundling implies a less effective regulation, but it reduces the degree of market distortion caused by the difference between marginal costs and average costs (= regulated prices of network usage). We find that the necessary condition is not satisfied for realistic values of the relevant parameters, i.e. legal unbundling leads to lower costumer prices than ownership unbundling in most relevant markets. --Unbundling,vertical integration,Cournot competition

The Axiomatic Foundation of Logit

Multinomial logit is the canonical model of discrete choice but widely criticized for requiring functional form assumptions as foundation. The present paper shows that logit is behaviorally founded without such assumptions. Logit's functional form obtains if relative choice probabilities are independent of irrelevant alternatives and invariant to utility translation, to relabeling options (presentation independence), and to changing utilities of third options (context independence). Reviewing behavioral evidence, presentation and context independence seem to be violated in typical experiments, though not IIA and translation invariance. Relaxing context independence yields contextual logit (Wilcox, 2011), relaxing presentation independence allows to capture "focality" of options

An axiomatic foundation of conditional logit

Breitmoser Y. An axiomatic foundation of conditional logit. ECONOMIC THEORY. 2020.This paper considers a decision maker choosing from a set of options when options have multiple real-valued attributes. Assuming DM chooses all options with positive probability, four invariance assumptions are necessary and sufficient for choice probabilities to take McFadden's conditional logit form: independence of irrelevant alternatives, translation invariance, presentation independence and context independence. Variations on these assumptions yield generalized logit and contextual logit models. This shows that even specific logit models have behavioral foundations in simple invariance assumptions involving observables only, which therefore are directly testable

Discrete Choice with Presentation Effects

Experimenters have to make theoretically irrelevant decisions concerning user interfaces and ordering or labeling of options. Such presentation decisions affect behavior and cause results to appear contradictory across experiments, obstructing utility estimation and policy recommendations. The present paper derives a model of choice allowing analysts to control for both presentation effects and stochastic errors in econometric analyses. I test the model in a comprehensive re-analysis of dictator game experiments. Controlling for presentation effects, preference estimates are consistent across experiments and predictive out-of-sample, highlighting the fundamental role of presentation for choice, and this notwithstanding the possibility of reliable estimation and prediction

Knowing Me, Imagining You:

Overbidding in auctions has been attributed to e.g. risk aversion, loser regret, level-k, and cursedness, relying on varying identifying assumptions. I argue that "type projection'" organizes these findings and largely captures observed behavior. Type projection formally models that people tend to believe others have object values similar to their own - a robust psychological phenomenon that naturally applies to auctions. First, I show that type projection generates the main behavioral phenomena observed in auctions, including increased sense of competition ("loser regret") and broken Bayesian updating ("cursedness"). Second, re-analyzing data from seven experiments, I show that type projection explains the stylized facts of behavior across private and common value auctions. Third, in a structural analysis relaxing the identifying assumptions made in earlier studies, type projection consistently captures behavior best, in-sample and out-of-sample. The results reconcile bidding patterns across conditions and have implications for behavioral and empirical analyses as well as policy