Repeated Multimarket Contact with Private Monitoring: A Belief-Free Approach

This paper studies repeated games where two players play multiple duopolistic games simultaneously (multimarket contact). A key assumption is that each player receives a noisy and private signal about the other's actions (private monitoring or observation errors). There has been no game-theoretic support that multimarket contact facilitates collusion or not, in the sense that more collusive equilibria in terms of per-market profits exist than those under a benchmark case of one market. An equilibrium candidate under the benchmark case is belief-free strategies. We are the first to construct a non-trivial class of strategies that exhibits the effect of multimarket contact from the perspectives of simplicity and mild punishment. Strategies must be simple because firms in a cartel must coordinate each other with no communication. Punishment must be mild to an extent that it does not hurt even the minimum required profits in the cartel. We thus focus on two-state automaton strategies such that the players are cooperative in at least one market even when he or she punishes a traitor. Furthermore, we identify an additional condition (partial indifference), under which the collusive equilibrium yields the optimal payoff.Comment: Accepted for the 9th Intl. Symp. on Algorithmic Game Theory; An extended version was accepted at the Thirty-Fourth AAAI Conference on Artificial Intelligence (AAAI-20

Multimarket contact in pharmaceutical markets

We analyze the effect of multimarket contact on the pricing behavior of pharmaceutical firms controlling for different levels of regulatory constraints using the IMS MIDAS database for the industry. Theoretically, under product differentiation, firms may find it profitable to allocate their market power among markets where they are operating, specifically from more collusive to more competitive ones. We present evidence for nine OECD countries suggesting the existence of a multimarket effect for more market friendly countries (U.S. and Canada) and less regulated ones (U.K., Germany, Netherlands), while the results are more unstable for highly regulated countries with some countries being consistent with the theory (France) while others contradicting it (Japan, Italy and Spain). A key result indicates that in the latter countries, price constraints are so intense, that there is little room for allocating market power. Thus equilibrium prices are expected in general to be lower in regulated countries.Pharmaceutical prices, Multimarket Contact, Regulation

Leniency Programs for Multimarket Firms: The Effect of Amnesty Plus on Cartel Formation

We examine the effect of the Amnesty Plus policy on firms' incentives to engage in cartel activities. Amnesty Plus is a proactive antitrust enforcement strategy aimed at attracting amnesty applications by encouraging firms already convicted in one market to report collusive agreements in other markets. It has been heavily advertised that Amnesty Plus weakens cartel stability. We show to the contrary that Amnesty Plus does not always have this desirable effect. Only under specific conditions, Amnesty Plus deters a cartel which would have been sustainable under an antitrust policy without Amnesty Plus. Otherwise, Amnesty Plus is either neutral or even stabilizes a cartel. We also show that firms can exploit their multimarket contact to reduce the effectiveness of the Amnesty Plus policy.Amnesty Plus; Leniency Program; Multimarket Contact; Antitrust Policy

Multimarket Contact in Pharmaceutical Markets

The purpose of this paper is to analyze the effect of multimarket contact on the behavior of pharmaceutical firms controlling for different levels of regulatory constraints using IMS MIDAS database. Theoretically, firms that meet in several markets are expected to be capable of sustaining implicitly more profitable out- comes, even if perfect monitoring is not possible. Firms may find it profitable to redistribute their market power among markets where they are operating. We present evidence for nine OECD countries with different degrees of regulation and show that regulation affects the importance of economic forces on firms' price setting behavior. Furthermore, our results confirms the presence of the predictions of the multimarket theory for more market friendly countries (U.S. and Canada) and less regulated ones (U.K., Germany, Netherlands), in contrast, for highly regulated countries (Japan, France, Italy and Spain) the results are less clear with some countries beingPharmaceutical prices, Multimarket Contact, Regulation

Market Power, Multimarket Contact and Pricing: Some Evidence from the US Automobile Market

Multimarket contact is perceived to be one of those factors, which can facilitate and sustain implicit collusive (cooperative) arrangements. This paper attempts to develop new approaches to study the interdependence of firm behaviour across markets, especially in the context of differentiated products industries. I analyse the principle of conducting a test of the mutual forbearance hypothesis, and its application using particular data. The multimarket contact effects are studied within a structural oligopoly model for differentiated products for the US automobile market on the basis of the aggregate product-level data for 2001-2003. Some support has been found that multimarket contact may influence competition in the automobile market and increase the firms' strategic interdependence. This effect is, however, difficult to disentangle from the effect of the market concentration in the US automobile market (dominance of the market by the American Big Three) on the firm behaviour, which could also facilitate collusion. In other words, it is difficult to argue whether coordination is due to market concentration, or due to multimarket contact, or both. Concentration is argued to foster the slack, which is transferred through the multimarket contact. --multimarket contact,collusion,automobile industry,test for non-nested hypothesis,menu test,structural oligopoly models

Networks of Relations

We model networks of relational (or implicit) contracts, exploring how sanctioning power and equilibrium conditions change under different network configurations and information transmission technologies. In our model, relations are the links, and the value of the network lies in its ability to enforce cooperative agreements that could not be sustained if agents had no access to other network members’ sanctioning power and information. We identify conditions for network stability and in-network information transmission as well as conditions under which stable subnetworks inhibit more valuable larger networks

Networks of Relations

We model networks of relational (or implicit) contracts, exploring how sanctioning power and equilibrium conditions change under different network configurations and information transmission technologies. In our model, relations are the links, and the value of the network lies in its ability to enforce cooperative agreements that could not be sustained if agents had no access to other network members’ sanctioning power and information. We identify conditions for network stability and in-network information transmission as well as conditions under which stable subnetworks inhibit more valuable larger networks.Networks; Relational Contracts; Indirect Multimarket Contact; Social Capital.

Leniency programs for multimarket firms: The effect of Amnesty Plus on cartel formation

We examine the effect of the Amnesty Plus policy on the incentives of firms to engage in cartel activities. Amnesty Plus is aimed at attracting amnesty applications by encouraging firms, convicted in one market, to report their collusive agreements in other markets. It has been vigorously advertised that Amnesty Plus weakens cartel stability. We show to the contrary that Amnesty Plus may not have this desirable effect, and, if improperly designed, may even stabilize a cartel. We suggest a simple discount-setting rule to avoid this anticompetitive effect.Amnesty Plus, Leniency program, multimarket contact, antitrust policy

Market power, multimarket contact and pricing : some evidence from the US automobile market

Multimarket contact is perceived to be one of those factors, which can facilitate and sustain implicit collusive (cooperative) arrangements. This paper attempts to develop new approaches to study the interdependence of firm behaviour across markets, especially in the context of differentiated products industries. I analyse the principle of conducting a test of the mutual forbearance hypothesis, and its application using particular data. The multimarket contact effects are studied within a structural oligopoly model for differentiated products for the US automobile market on the basis of the aggregate product-level data for 2001-2003. Some support has been found that multimarket contact may influence competition in the automobile market and increase the firms’ strategic interdependence. This effect is, however, difficult to disentangle from the effect of the market concentration in the US automobile market (dominance of the market by the American Big Three) on the firm behaviour, which could also facilitate collusion. In other words, it is difficult to argue whether coordination is due to market concentration, or due to multimarket contact, or both. Concentration is argued to foster the slack, which is transferred through the multimarket contact