@misc{Fleicher_Karlheinz_Statistically_2019, author={Fleicher, Karlheinz and Nietert, Bernhard}, identifier={DOI: 10.15611/sps.2019.17.01}, year={2019}, rights={Pewne prawa zastrzeżone na rzecz Autorów i Wydawcy}, publisher={Wydawnictwo Uniwersytetu Ekonomicznego we Wrocławiu}, description={Śląski Przegląd Statystyczny = Silesian Statistical Review, 2019, Nr 17 (23), s. 9-29}, language={eng}, abstract={Semivariance is an intuitive risk measure because it concentrates on the shortfall below a target and not on total variation. To successfully use semivariance in practice, however, a statistical estimator of semivariance is needed; Josephy and Aczel provide such an estimator. Unfortunately, they have not correctly proven asymptotic unbiasedness and mean squared error consistency of their estimator since their proof contains a mistake. This paper corrects the computational mistake in Josephy-Aczel’s original proof and, that way, allows researchers and practitioners in the field of downside portfolio selection, hedging, downside asset pricing, risk measurement in a regulatory context, and performance measurement to work with a meaningfully specified downside measure}, title={Statistically (optimal) estimators of semivariance: A correction of Josephy-Aczel’s proof}, type={artykuł}, keywords={risk analysis, semivariance, statistical estimation, analiza ryzyka, semiwariancja, estymacja statystyczna}, }