Gábor Kőrösi

Firms' Price Markups and Returns to Scale in Imperfect Markets: Bulgaria and Hungary

Under perfect competition and constant returns to scale, firms producing homogeneous products set their prices at their marginal costs which also equal their average costs. However, the departure from these standard assumptions has important implications with respects to the derived theoretical results and the validity of the related empirical analysis. In particular, monopolistic firms will charge a markup over their marginal costs. We show that firms??? markups tend to be directly associated with the employed production technology, more specifically with their returns to scale. Accordingly, we analyze the implications for the markup ratios from the incidence of non-constant returns to scale. We present quantitative results illustrating the effect of the returns to scale index on the firms??? price markups, as well as the relationship between the two indicators, on the basis of firm-level data for Bulgarian and Hungarian manufacturing firms.

A lány továbbra is szolgál

Mellar Tamas kozelmultbeli cikkeben az empirikus makrogazdasagtan velt vagy valos problemaiert, az elmult evek hibasnak bizonyult makrogazdasagi előrejelzeseiert egyedul az okonometriaban talalta meg a felelőst. Nem mehetek el szo nelkul e tulzo allitas mellett. Az empirikus makrogazdasagtan es az okonometriai modszertan kapcsolatanak nehany fontos kerdeseről irok, kulonos tekintettel az aggregalt idősorok hasznalatanak problemaira. Felvazolom, hogy miert nincs ertelme gazdasagi idősorok trendbecslesenek, kiterek az egyensulyi modellekre, vegul megmutatom az előrejelzesek keszitesenek felteteleit es korlatait.* Journal of Economic Literature (JEL) kod: C01, C5, E17, E32, E37.

High Frequency Data Analysis in an Emerging and a Developed Market

We compare distributional properties of high frequency (tick by tick) returns of stocks traded at the NASDAQ, NYSE, and BSE (Budapest Stock Exchange). In particular, we model returns with a mixture of a degenerate (zero) and a symmetric stable distribution. We measure time with the number of successive price changes on the market and study the convergence of the index of stability on increasing time horizons. We apply results to calculate expected waiting times to reach given levels of value at risk.