English to Czech Bus/Financial Other

At short horizons, returns tend to be either close to the mean or to take large values. By contrast, for longer horizons the bell and the tails of the return distribution become thinner, while the intermediate regions gain mass. These nonlinearities are also apparent in the behaviour of return moments, as documented by the expanding literature on power variation. In many financial series, the moments of the absolute value of returns vary as a power function of the frequency of observation. Děkuji.