We experimentally compare collusive behaviors in first-price sealed-bid auctions without and with a reserve price. Before the auction begins, a bidder may offer a bribe to the other bidder, in exchange for a commitment not to participate in the auction. We find that the average offer and the rate of successful bribes are significantly lower in the treatment with a reserve price. These results are largely due to responding bidders who demand a greater share of the benefit from collusion. Although imposing a reserve price reduces efficiency, its optimality and bribe deterrence shift the surplus from the bidders to the seller.

On the basis of evidence of past oligopoly experiments, we argue that there is often significantly more tacit collusion in Bertrand price-choice than in Cournot quantity-choice markets.

This paper studies the vulnerability of the pivotal mechanism with respect to manipulation by groups. In a lab experiment, groups decide on the implementation of various alternatives, some of which imply opposite interests for the two subgroups. We investigate the occurrence of tacit and explicit collusion by allowing for communication within subgroups in one treatment and prohibiting it in another. Even though all agents’ preferences are common knowledge and there exists a simple symmetric collusive strategy for one subgroup, we find little evidence for tacit collusion. Only when explicit communication is allowed, collusion is established. A behavioral model using quantal response equilibrium in which subjects have beliefs over the correlation of errors of same-type subjects helps explain the main features of our data.

We explore the effects of the provision of an information-processing instrument—payoff tables—on behavior in experimental oligopolies. In one experimental setting, subjects have access to payoff tables whereas in the other setting they have not. It turns out that this minor variation in presentation has non-negligible effects on participants’ behavior, particularly in the initial phase of the experiment. In the presence of payoff tables, subjects tend to be more cooperative. As a consequence, collusive behavior is more likely and quickly to occur.

This dissertation comprises three independent essays that analyze pricing behavior in experimental duopoly markets.

The first essay examines whether the content of buyer information and the timing of its dissemination affects seller market power. We construct laboratory markets with differentiated goods and costly buyer search in which sellers simultaneously post prices. The experiment varies the information on price or product characteristics that buyers learn under different timing assumptions (pre- and post-search), generating four information treatments. Theory predicts that price information lowers the equilibrium price, but information about product characteristics increases the equilibrium price. That is, contrary to simple intuition, presence of informed buyers may impart a negative externality on other uninformed buyers. The data support the model's negative externality result when sellers face a large number of robot buyers that are programmed to search optimally. Observed prices conform to the model's comparative statics and are broadly consistent with predicted levels. With human buyers, however, excessive search instigates increased price competition and sellers post prices that are significantly lower than predicted.

The second essay uses experimental methods to demonstrate the anti-competitive potential of price-matching guarantees in both symmetric and asymmetric cost duopolies. When costs are symmetric, price-matching guarantees increase the posted prices to the collusive level. With asymmetric costs, guaranteed prices remain high relative to prices without the use of guarantees, but the overall ability of guarantees to act as a collusion facilitating device depends on the relative cost difference. Fewer guarantees, combined with lower average prices, suggest that cost asymmetries may discourage collusion.

The third essay investigates the effect of firm size asymmetry on the emergence of price leadership in a homogeneous good duopoly. With discounting, the unique subgame-perfect equilibrium predicts that the large firm will emerge as the endogenous price leader. Independent of the level of size asymmetry, the laboratory data indicates that price leadership by the large firm is one of the most frequently observed timings of price announcement. In most cases, however, it comes second to simultaneous pricesetting. This tendency to wait for the other firm to announce its price is especially strong when the level of size asymmetry between firms is low. We attribute the lower than expected frequency of price leadership to coordination failure, which is further compounded by elements of inequity aversion.

Agency theory has established that appropriate incentives can reconcile the diverging interests of the principal and the agent. Focusing on three applications, this dissertation evaluates the empirical relevance of these results when a third party interacts with the primary contract. The analyses provided rely on either laboratory or natural experiments.

First, corruption is analyzed as a two-contract situation: a delegation contract between a Principal and an Agent and a corruption pact concluded between this Agent and a third player, called Briber. A survey of the recent microeconomic literature on corruption first highlights how corruption behavior results from the properties of those two agreements. We thereafter show that the Agent faces a conflict in reciprocities due to those two conflicting agreements. The resulting delegation effect, supported by observed behavior in our three-player experimental game, could account for the deterrence effect of wages on corruption.

Second, health care is governed by contradictory objectives: patients are mainly concerned with the health provided, whereas containing health care costs is the primary goal of health care administrators. We provide further insights into the ability of incentives to balance these two competing objectives. In this matter, our theoretical and econometric analysis evaluates how a new mixed compensation scheme, introduced in Quebec in 1999 as an alternative to fee-for-services, has affected physicians’ practice patterns. Free switching is shown to be an essential feature of the reform, since it implements screening between physicians.

Finally, the demand for underground work departs from the traditional Beckerian approach to illegal behavior, due to the dependence of benefits from illegality on competitors’ behavior. We set up a theoretical model in which the demand for underground work from all producers competing on the same output market is analyzed simultaneously. We first show that competition drastically undermines the individual benefits of tax evasion. At equilibrium, each firm nonetheless chooses evasion with a positive probability, strictly lower than one. This Bertrand curse could then account for the “tax evasion puzzle” i.e. the overprediction of evasion in models that ignore market interactions. We thereafter show that allowing firms to denounce competitors’ evasion is not likely to solve this curse—by providing a credible threat against price cuts, it fosters illegal work. Empirical evidence from a laboratory experiment confirms these predictions. Without denunciation, experimental firms often choose evasion whereas evasion benefits are canceled out by competition. When introduced, denunciation is rarely used by firms, but the threat makes evasion profitable.

The traditional description of Contestability theory considers the importance of potential entry threats in disciplining the incumbent firm in a natural monopoly market. Such a description however overlooks an important element in strategic interaction, that of an entrant firm having its own home market. Adding a home market to the model can critically alter conclusions and equilibrium predictions of market entry in a contestable market monopoly.

In this thesis the role of entry threats in a contestable market is analyzed and evaluated in a game theoretic framework where the incumbent and the entrant firm each has its own home market and is a potential entrant in the other market. Equilibrium predictions point out that in such a multi-market context where each firm has its own monopoly market, the disciplining effect of potential entry is weak. In contrast, entrants from competitive markets have its predicted disciplining effect on the monopolist incumbent.

I design a multi-market laboratory environment with contestable markets. Experimental results show that the threat of entry is the strongest when an entrant firm has a home market with very low or competitive returns. However, entrants and incumbents in symmetric monopoly home markets learn to cooperate tacitly to enjoy monopoly prices. I extend my analysis to an imperfectly contestable market with sunk entry cost and find similar results.

My main conclusion is as follows: the behavioral implication for hit-and-run entry in a contestable monopoly market is strong and robust provided the entrant is from a market earning normal returns or competitive returns. Even in the presence of a modest level of sunk entry cost, entrants from competitive markets enter for transient profit opportunities. This in turn generates the threat of entry and disciplines the incumbent in the natural monopoly market. However, when each firm has its own home market monopoly we observe mutual forbearance leading to high prices in both the perfectly contestable and imperfectly contestable monopoly markets.

Collusive agreements in the form of corporate cartels are complex structures. The involved firms need to agree on terms that are legally not enforceable. However, the interplay between the involved firms in a collusive agreement, i.e., the governance dimension within a cartel, has received surprisingly low attention. Using a comprehensive OECD dataset of 191 cartels from 2012 to 2018, this paper empirically demonstrates how polycentric governance within a cartel may possibly contribute to understanding its stability. It may be beneficial for the duration and lower sanctions imposed by competition authorities, especially for large cartels. By that, the paper sheds new light on two aspects: the entangled governance structures of corporate cartels and the relevance of the concept of polycentricity beyond public administration.