We examine the various senses in which economist use the term "rationality" and then outline some of the commonly drawn …

network without compromising prediction accuracy. We evaluate its performance by predicting the daily volatility and closing …

and volatility regimes. Using cointegrated price data, it is shown that increasing the number of assets in a portfolio … supports the proftability of the HFRA in an up-trend and reduces the potential loss of the HFRA in a down-trend in a high-volatility … environment. For low-volatility regimes, although increasing portfolio size marginally enhances the HFRA's proftability, the …