Ownership structure and firm performance in Russia: the case of blue chips of the stock market

Based on panel data from 1995.1997, the paper focusses on the impact of ownership concentration on the performance of Russian non-financial privatised companies that constitute the group of .blue chips. of the country.s stock market. We consider three indicators of company performance . labour productivity, profitability, and Tobins.s q . and employ instrumental variables technique to correct regression results for endogeneity of ownership. We find that ownership concentration positively affects labour productivity, but has a negative impact on Tobins.s q. The relationship between ownership concentration and profitability follows a U-shaped pattern with the turning point at 56% concentration. These findings imply that ownership concentration results in higher technical efficiency of enterprises, but the benefits from productivity improvements do not accrue to all shareholders. This is consistent with the expropriation hypothesis that large owners use their power to extract private benefits of control

Numerical test for hyperbolicity of chaotic dynamics in time-delay systems

We develop a numerical test of hyperbolicity of chaotic dynamics in time-delay systems. The test is based on the angle criterion and includes computation of angle distributions between expanding, contracting and neutral manifolds of trajectories on the attractor. Three examples are tested. For two of them previously predicted hyperbolicity is confirmed. The third one provides an example of a time-delay system with nonhyperbolic chaos.Comment: 7 pages, 5 figure

Hyperbolic Chaos of Turing Patterns

We consider time evolution of Turing patterns in an extended system governed by an equation of the Swift-Hohenberg type, where due to an external periodic parameter modulation long-wave and short-wave patterns with length scales related as 1:3 emerge in succession. We show theoretically and demonstrate numerically that the spatial phases of the patterns, being observed stroboscopically, are governed by an expanding circle map, so that the corresponding chaos of Turing patterns is hyperbolic, associated with a strange attractor of the Smale-Williams solenoid type. This chaos is shown to be robust with respect to variations of parameters and boundary conditions.Comment: 4 pages, 4 figure

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