Laussel

Publications

Simple centrifugal incentives in spatial competitionJournal articleDimitrios Xefteris, Didier Laussel et Michel Le Breton, International Journal of Game Theory, Volume 46, Issue 2, pp. 357-381, 2017

This paper studies the effects of introducing centrifugal incentives in an otherwise standard Downsian model of electoral competition. First, we demonstrate that a symmetric equilibrium is guaranteed to exist when centrifugal incentives are induced by any kind of partial voter participation (such as abstention due to indifference, abstention due to alienation, etc.) and, then, we argue that: (a) this symmetric equilibrium is in pure strategies, and it is hence convergent, only when centrifugal incentives are sufficiently weak on both sides; (b) when centrifugal incentives are strong on both sides (when, for example, a lot of voters abstain when they are sufficiently indifferent between the two candidates) players use mixed strategies—the stronger the centrifugal incentives, the larger the probability weight that players assign to locations near the extremes; and (c) when centrifugal incentives are strong on one side only—say for example only on the right—the support of players’ mixed strategies contain all policies except from those that are sufficiently close to the left extreme.

Network effects, aftermarkets and the Coase conjecture: A dynamic Markovian approachJournal articleDidier Laussel, Ngo Van Long et Joana Resende, International Journal of Industrial Organization, Volume 41, Issue C, pp. 84-96, 2015

This paper investigates the expansion of the network of a monopolist firm that produces a durable good and is also involved in the corresponding aftermarket. We characterize the Markov Perfect Equilibrium of the continuous time dynamic game played by the monopolist and the forward-looking consumers, under the assumption that consumers benefit from the subsequent expansion of the network. The paper contributes to the theoretical discussion on the validity of the Coase conjecture, analyzing whether Coase's prediction that the monopolist serves the market in a “twinkling of an eye” remains valid in our setup. We conclude that the equilibrium network development may actually be gradual, contradicting Coase's conjecture. We find that a necessary condition for such a result is the existence of aftermarket network effects that accrue (at least partly) to the monopolist firm.

Dynamic price competition in aftermarkets with network effectsJournal articleDidier Laussel et Joana Resende, Journal of Mathematical Economics, Volume 50, Issue C, pp. 106-118, 2014

This paper studies the dynamic price competition between two firms that sell horizontally differentiated durable goods and, subsequently, provide exclusive complementary goods and services to their customers. The paper analyzes how optimal pricing strategies are affected by the existence of network effects associated with the size of firms' consumer base. The interaction is thoroughly analyzed as a continuous time linear-quadratic differential game. We provide a necessary and sufficient condition for the existence of a unique duopoly equilibrium in affine strategies. When this condition holds, we show that optimal pricing strategies crucially depend on the nature of the network effects.

Regulating a manager whose empire-building preferences are private informationJournal articleAna Borges, Joao Correia-da-Silva et Didier Laussel, Journal of Economics, Volume 111, Issue 2, pp. 105-130, 2014

We obtain the optimal contract for the government (principal) to regulate a manager (agent) who has a taste for empire-building that is his/her private information. This taste for empire-building is modeled as a utility premium that is proportional to the difference between the contracted output and a reference output. We find that output is distorted upward when the manager's taste for running large firms is weak, downward when it is strong, and equals a reference output when it is intermediate (in this case, the participation constraint is binding). We also obtain an endogenous reference output (equal to the expected output, which depends on the reference output), and find that the response of output to cost is null in the short-run (in which the reference output is fixed), whenever the manager's type is in the intermediate range, and negative in the long-run (after the adjustment of the reference output to equal expected output). Copyright Springer-Verlag Wien 2014

Advertising Spillovers and Market StructureJournal articleNada Ben Elhadj, Rim Lahmandi-Ayed et Didier Laussel, Recherches économiques de Louvain, Volume 80, Issue 3, pp. 51-98, 2014

In this paper we characterize the equilibrium of a duopoly market which exhibits advertising spillovers. Interestingly, we prove that the relevant distinction is not between pure positive and pure negative advertising spillovers but between strong positive spillovers and weakly positive or negative spillovers. Moreover, we prove that, depending on the extent of advertising spillovers and the agency advertising cost, we may obtain at equilibrium either two active advertisers or only one advertiser that may even push its rival out of the product market. Thus advertising and the spillovers induced from it may be a source of a monopoly situation, hence an asymmetric outcome may result from an initially symmetric situation.

The sources of protectionist drift in representative democraciesBook chapterDidier Laussel et Raymond Riezman, In: The Tricontinental Series on Global Economic Issues: Volume 3 International Trade Agreements and Political Economy, 2013-06, pp. 225-246, World Scientific Publishing Co. Pte. Ltd., 2013

We analyze a two country-two good model of international trade in which citizens in each country differ by their specific factor endowments. The trade policy in each country is set by the politician who has been elected by the citizens in a previous stage. Due to a delegation effect citizens generally favor candidates who are more protectionist than they are. The one-candidate-per-country equilibria exhibit a "protectionist drift" owing to this delegation effect. In addition, we find an additional source of protectionist drift that we call the "abstention effect". Not only do candidates wish to delegate to more protectionist colleagues, but these more protectionist colleagues who can win election, prefer still more protectionist candidates than themselves. Therefore, they have an incentive to abstain, that is, not run for election. We show that because of this abstention effect there exists a range of electable citizens all of whom are more protectionist than the median voter's most preferred candidate. We extend the analysis allowing two-candidate equilibria and the possibility that there are costs and benefits of holding office.

Market Games in Successive OligopoliesJournal articleJean J. Gabszewicz, Didier Laussel, Tanguy van Ypersele et Skerdilajda Zanaj, Journal of Public Economic Theory, Volume 15, Issue 3, pp. 397-410, 2013

In this paper we first introduce an approach relying on market games to examine how successive oligopolies operate between downstream and upstream markets. This approach is then compared with the traditional analysis of oligopolistic interaction in successive markets. The market outcomes resulting from the two approaches are analysed under di¤erent technological regimes, decreasing vs constant returns.

Multidimensional Screening with Complementary Activities: Regulating a Monopolist with Unknown Cost and Unknown Preference for Empire BuildingJournal articleAna Pinto Borges, Didier Laussel et Joao Correia-da-Silva, Games, Volume 4, Issue 3, pp. 532-560, 2013

We study the optimal regulation of a monopolist when intrinsic efficiency (intrinsic cost) and empire building tendency (marginal utility of output) are private information, but actual cost (the difference between intrinsic cost and effort level) is observable. This is a problem of multidimensional screening with complementary activities. Results are not only driven by the prior probabilities of the four possible types, but also by the relative magnitude of the uncertainty along the two dimensions of private information. If the marginal utility of output varies much more (less) across managers than the intrinsic marginal cost, there is empire building (efficiency) dominance. In that case, an inefficient empire builder produces more (less) and at lower (higher) marginal cost than an efficient money-seeker. It is only when variabilities are similar that there may be the natural ranking of activities (empire builders produce more, while efficient managers produce at a lower cost).

Large shareholders, monitoring, and ownership dynamics: Toward pure managerial firms?Journal articleAmal Hili, Didier Laussel et Ngo Van Long, Journal of Economic Dynamics and Control, Volume 37, Issue 3, pp. 666-679, 2013

We study ownership dynamics when the manager and the large shareholder, both risk neutral, simultaneously choose effort and monitoring level respectively to serve their non-congruent interests.We show that there is a wedge between the valuation of shares by atomistic shareholders and the large shareholder's valuation. At the Markov-perfect equilibrium, the large shareholder divests her shares. If the incongruence of their interests is mild, divestment is drastic: all her shares are sold immediately. If their interests diverge sharply, the divestment is gradual in order to prevent a sharp fall in share price. In the limit the firm becomes purely managerial.

Vertical Disintegration: A Dynamic Markovian ApproachJournal articleDidier Laussel et Ngo Van Long, Journal of Economics & Management Strategy, Volume 21, Issue 3, pp. 745-771, 2012

No abstract is available for this item.