Strong Nash Equilibrium in Cournot and Bertrand Oligopolies
This paper investigates the existence of strong Nash equilibria (SNE) in Cournot and Bertrand oligopoly models. Given the concavity and continuity of payoffs, I derive the necessary and sufficient conditions for the existence of SNE in these non-cooperative games.
This is the first paper on consumer search where the cost of going back to stores already searched is explicitly taken into account. We show that the optimal sequential search rule under costly second visits is very different from the traditional reservation price rule in that it is nonstationary and not independent of previously sampled prices. We explore the implications of costly second visits on market equilibrium in two celebrated search models. In the Wolinsky model some consumers search beyond the first firm and in this class of models costly second visits do make a substantive difference: equilibrium prices under costly second visits can both be higher and lower than their perfect recall analogues. In the oligopoly search model of Stahl where consumers do not search beyond the first firm, there remains a unique symmetric equilibrium that has firms use pricing strategies that are identical to the perfect recall case.
Many industries are made of a few big firms, which are able to manipulate the market outcome, and of a host of small businesses, each of which has a negligible impact on the market. We provide a general equilibrium framework that encapsulates both market structures. Due to the higher toughness of competition, the entry of big firms leads them to sell more through a market expansion effect generated by the shrinking of the monopolistically competitive fringe. Furthermore, social welfare increases with the number of big firms because the pro-competitive effect associated with entry dominates the resulting decrease in product diversity.
In the paper two types of games are considered: the infinity repeated games and multistage games with prescribed duration. The notion of Partially Strong Nash Equilibrium (PSNE) is introduced and the existence of (PSNE) proved for the version of the game with specially defined payoffs along cooperative trajectory.
We study Bertrand competition models with incomplete information about rivals' costs, where uncertainty is given by independent identically distributed random variables. It turns out that Bayesian Nash equilibria of the simplest of these games are described as Cournot prices. Then we discuss general conditions when Cournot prices give Bayesian Nash equilibria for Bertrand games with incomplete information about rivals' costs.
«Менеджерлерге арнал#ан экономика» кітабы о9ырманды зама-
науи 9о#амда аса 9ажетті болып табылатын ?рі экономикалы9 ойлауды
9алыптастыру#а ы9пал ететін микро ж?не макроэкономика моделдеріні/
негізгі M#ым-тOсініктерімен таныстырады. Атал#ан о9улы9ты/ ерекшелігі,
мMнда теориялы9 моделдер мен тMжырымдарды/ практикалы9 9ызмет ба-
рысында пайдаланылуына басты назар аударылады. Экономист-аналитик-
терге, сарапшылар#а арнал#ан экономикалы9 теория бойынша д?стOрлі
о9улы9тардан айырмашылы#ы, «Менеджерлерге арнал#ан экономика» биз-
нес 9Mрылымдарда 9ызмет ететін немесе осы салада жMмыс жасауды жоспар-
лап жOрген практик мамандар#а арнал#ан. Кітапта іс жOзінде 9ызмет ат9арып
жат9ан нары9тар мен компанияларды/ на9ты мысалдары, тапсырмалар
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of Business Administration (MBA)» білім беру ба#дарламасы бойынша 9осымша
к?сіби білім алушылар#а арнал#ан. Сонымен 9атар экономика саласына
9ызы#ушылы9 танытатын 9алы/ кHпшілік 9ауым#а — студенттерге, экономика
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The article considers the processes of progress in production and service sectors and answers the question how and thanks to what service sector of Russian economy left the productive one behind (concerning contribution in GDP of our country). The rates of development of service sector turned out to be so high firstly - as a reason of peculiarities of new Russian economy, which historically was built on the market principles and was developing in conditions of investment resources deficit, secondly - as a reason of system differences between «physical» goods and services as an object of sale. Nowadays Russia faces an unusual symbiosis: effective service companies, operating in hard competitive sphere with average profitability and non-affective from the point of management industrial companies, which thanks to monopolistic pricing have great profitability, providing profits of Russian budget and determining a macroeconomic situation.
The paper examines the structure, governance, and balance sheets of state-controlled banks in Russia, which accounted for over 55 percent of the total assets in the country's banking system in early 2012. The author offers a credible estimate of the size of the country's state banking sector by including banks that are indirectly owned by public organizations. Contrary to some predictions based on the theoretical literature on economic transition, he explains the relatively high profitability and efficiency of Russian state-controlled banks by pointing to their competitive position in such functions as acquisition and disposal of assets on behalf of the government. Also suggested in the paper is a different way of looking at market concentration in Russia (by consolidating the market shares of core state-controlled banks), which produces a picture of a more concentrated market than officially reported. Lastly, one of the author's interesting conclusions is that China provides a better benchmark than the formerly centrally planned economies of Central and Eastern Europe by which to assess the viability of state ownership of banks in Russia and to evaluate the country's banking sector.
The paper examines the principles for the supervision of financial conglomerates proposed by BCBS in the consultative document published in December 2011. Moreover, the article proposes a number of suggestions worked out by the authors within the HSE research team.