A kompetitív piac közelítése sokszereplős Cournot-oligopóliumokkal

Mikroökonómia tankönyvekből és példatárakból ismert, hogy egy homogén termékű Cournot-oligopol piacon a termelők számának növelésével közelíthető a kompetitív piac. Az iskolapéldában lineáris keresleti görbét és állandó egységköltséget tételeznek fel. Az irodalomban több munka is foglalkozik az említett feltételek enyhítésével. Jelen dolgozatban egy új, egyszerű approximációs tételt igazolunk. Az első szakaszban áttekintjük a Cournot-oligopol játék egyensúlyának egzisztenciájára és a kompetitív piac Cournot-oligopóliumokkal történő approximálhatóságára vonatkozó eredményeket. Az egyensúly létezésével kapcsolatos eredményeket felhasználjuk a második szakaszban található approximációs tételünkhöz, amit aztán összevetünk az irodalomban található approximációs tételekkel.

Licensing endogenous cost-reduction in a differentiated Stackelberg model

In this paper we consider a differentiated Stackelberg model, when the leader firm engages in an R&D process that gives an endogenous cost-reducing innovation. The aim is to study the licensing of the cost-reduction by a two-part tariff. By using comparative static analysis, we conclude that the degree of the differentiation of the goods plays an important role in the results. We also do a direct comparison between our model and Cournot duopoly model.

Stochastic short-term maintenance scheduling of GENCOs in an oligopolistic electricity market

In the proposed model, the independent system operator (ISO) provides the opportunity for maintenance outage rescheduling of generating units before each short-term (ST) time interval. Long-term (LT) scheduling for 1 or 2 years in advance is essential for the ISO and the generation companies (GENCOs) to decide their LT strategies; however, it is not possible to be exactly followed and requires slight adjustments. The Cournot-Nash equilibrium is used to characterize the decision-making procedure of an individual GENCO for ST intervals considering the effective coordination with LT plans. Random inputs, such as parameters of the demand function of loads, hourly demand during the following ST time interval and the expected generation pattern of the rivals, are included as scenarios in the stochastic mixed integer program defined to model the payoff-maximizing objective of a GENCO. Scenario reduction algorithms are used to deal with the computational burden. Two reliability test systems were chosen to illustrate the effectiveness of the proposed model for the ST decision-making process for future planned outages from the point of view of a GENCO.

Licensing in an international market

We study the effects of entry of a foreign firm on domestic welfare in the presence of licensing, when the entrant is technologically superior to the incumbent. We show that foreign entry increases domestic welfare for sufficiently large technological differences between the firms under both fixed-fee licensing and royalty licensing.

Simultaneous decisions or leadership in an international competition

In this paper, we study an international market with demand uncertainty. The model has two stages. In the first stage, the home government chooses an import tariff to maximize the revenue. Then, the firms engage in a Cournot or in a Stackelberg competition. The uncertainty is resolved between the decisions made by the home government and by the firms. We compare the results obtained in the three different ways of moving on the decision make of the firms.

Two-production-period in a duopoly with nonprofit and for-profit firms

We investigate endogenous roles in a competition between a nonprofit firm and a for-profit firm in a homogeneous goods market, by allowing two production periods. We find that the Cournot-type equilibrium and one Stackelberg-type equilibrium where the nonprofit firm becomes the follower exist; however, another tackelberg-type equilibrium where the nonprofit firm becomes the leader does not exist.

Uncertainty in a mixed duopoly with quadratic costs

In this paper, we consider a mixed market with uncertain demand, involving one private firm and one public firm with quadratic costs. The model is a two-stage game in which players choose to make their output decisions either in stage 1 or stage 2. We assume that the demand is unknown until the end of the first stage. We compute the output levels at equilibrium in each possible role. We also determine ex-ante and ex-post firms’ payoff functions.

Desirable role in a price-setting international mixed duopoly

In this paper, we study the order of moves in a mixed international duopoly for differentiated goods, where firms choose whether to set prices sequentially or simultaneously. We discuss the desirable role of the public firm by comparing welfare among three games. We find that, in the three possible roles, the domestic public firm put a lower price, and then produces more than the foreign private firm.

Desirable role in an international duopoly model with tariffs

In this paper, we study an international market model in which the home government imposes a tariff on the imported goods. The model has two stages. In the first stage, the home government chooses an import tariff to maximize a function that cares about the home firm’s profit and the total revenue. Then, the firms engage in a Cournot or in a Stackelberg competition. We compare the results obtained in the three different ways of moving on the decision make of the firms.

Environmental and international tariffs in a mixed duopoly

In this paper, we study the effects of environmental and trade policies in an international mixed duopoly serving two markets, in which the public firm maximizes the sum of consumer surplus and its profit. We also analyse the effects of privatization. The model has two stages. In the first stage, governments choose environmental taxes and import tariffs, simultaneously. Then, the firms engage in a Cournot competition, choosing output levels for the domestic market and to export. We compare the results obtained in the three different ways of moving on the decision make of the firms.

International Stackelberg model with tariffs

This paper analyses the effects of tariffs on an international economy with a monopolistic sector with two firms, located in two countries, each one producing a homogeneous good for both home consumption and export to the other identical country. We consider a game among governments and firms. First, the government imposes a tariff on imports and then we consider the two types of moving: simultaneous (Cournot-type model) and sequential (Stackelberg-type model) decisions by the firms. We also compare the results obtained in each model.

Privatization in a mixed duopoly with environmental taxes

In this paper, we study the effects of environmental and privatization in a mixed duopoly, in which the public firm aims to maximize the social welfare. The model has two stages. In the first stage, the government sets the environmental tax. Then, the firms engage in a Cournot competition, choosing output and pollution abatement levels.

Privatization in an international mixed duopoly with environmental taxes

We study the effects of environmental and trade policies in an international duopoly serving two countries, with pollution abatement. This analysis is done in both mixed and privatized markets. The model has two stages: First, governments choose environmental taxes and import tariffs, simultaneously; then, the firms compete in the market by choosing output levels for the domestic market and to export and also abatement levels.

Government preference, environmental taxes and privatization

We analyse the relationship between the privatization of a public firm and government preferences for environmental tax revenue. The model that we consider is more general than the one consider in Wang and Wang (2009), in the sense that we put a larger weight in the environment tax revenue than on the other terms of the government's objective function. The model has two stages. In the first stage, the government sets the environmental tax. Then, the firms engage in a Cournot competition, choosing output and pollution abatement levels.

Privatization and social welfare in an international mixed Stackelberg duopoly

Competition between public and private firms exists in a range of industries like telecommunications, electricity, natural gas, airlines industries, as weel as services including hospitals, banking and education. Some authors studied mixed oligopolies under Cournot competition (firms move simultaneously) and some others considered Stackelberg models (firms move sequentially). Tomaru [1] analyzed, in a Cournot model, how decision-making upon cost-reducing R&D investment by a domestic public firm is affected by privatization when competing in the domestic market with a foreign firm. He shows that privatization of the domestic public firm lowers productive efficiency and deteriorates domestic social welfare. In this paper, we examine the same question but in a Stackelberg formulation instead of Cournot. The model is a three-stage game. In the first stage, the domestic firm chooses the amount of cost-reducing R&D investment. Then, the firms compete à la Stackelberg. Two cases are considered: (i) The domestic firm is the leader; (ii) The foreign firm is the leader. We show that the results obtained in [1] for Cournot competition are robust in the sence that they are also true when firms move sequentially.