A Kreps-Scheinkman-állítás érvényessége lineáris keresletű vegyes duopóliumok esetén (The Kreps and Scheinkman result remains valid for mixed duopolies with linear demand)

Vegyes oligopóliumoknak nevezzük az olyan piacszerkezeteket, amelyek esetében a magánvállalatok mellett állami vállalatok is tevékenykednek. A vegyes oligopóliumokban az állami vállalatok részben vagy egészében a társadalmi többletet kívánják maximalizálni. Olyan vegyes duopóliumot vizsgálunk, amelyben a vállalatok előbb kiépítik kapacitásaikat, majd meghatározzák termékük kínálati árát. Kreps-Scheinkman [1983] tisztán magánvállalatos duopóliumokra vizsgált ilyen két időszakos modellt, és megállapította, hogy az első időszaki egyensúlyi kapacitások megegyeznek az azonos költségszerkezetű és kínálati viszonyú Cournot-duopólium egyensúlyi kibocsátásaival. Tanulmányunkban Kreps-Scheinkman [1983] eredményét kiterjesztjük a vegyes duopóliumok - lineáris keresleti görbe és konstans egységköltségek melletti - esetére. _____ In mixed oligopolies, private firms compete with a public firm, which at least partially aims to maximize social surplus. The authors investigate mixed duopolies in which the firms first build capacities simultaneously and then set their prices simultaneously as well. For the same two-stage game with purely private firms Kreps and Scheinkman demonstrated in 1983 that the first-stage equilibrium capacities of the two-stage game are identical with the equilibrium outputs of the Cournot duopoly. This paper extends Kreps and Scheinkman's results to mixed duopolies with linear demands and constant unit costs. It is shown that quantity pre-commitment and Bertrand competition also yield to Cournot outcomes when a public firm is involved, not only in the case of private firms.

Examination of Inequalities in Hungary by Microsimulation in Consistency with Macro Data

Effective decision making uses various databases including both micro and macro level datasets. In many cases it is a big challenge to ensure the consistency of the two levels. Different types of problems can occur and several methods can be used to solve them. The paper concentrates on the input alignment of the households’ income for microsimulation, which means refers to improving the elements of a micro data survey (EU-SILC) by using macro data from administrative sources. We use a combined micro-macro model called ECONS-TAX for this improvement. We also produced model projections until 2015 which is important because the official EU-SILC micro database will only be available in Hungary in the summer of 2017. The paper presents our estimations about the dynamics of income elements and the changes in income inequalities. Results show that the aligned data provides a different level of income inequality, but does not affect the direction of change from year to year. However, when we analyzed policy change, the use of aligned data caused larger differences both in income levels and in their dynamics.