We test the hypothesis that, when thinking about allocating money to a stock, investors mentally represent the stock by the distribution of its past returns and then evaluate this distribution in the way described by prospect theory. In a simple model of asset prices in which some investors think in this way, a stock whose past return distribution has a high (low) prospect theory value earns a ...

We investigate the risk-return relation in international stock markets using realized variance constructed from MSCI (Morgan Stanley Capital International) daily stock price indices. In contrast with the capital asset pricing model, realized variance by itself provides negligible information about future excess stock market returns; however, we uncover a positive and significant risk-return tra...

The stochastic nature of financial markets is a barrier for successful portfolio management. Besides traditional Markowitz’s model, many other portfolio selection models in Bayesian and Non-Bayesian frameworks have been developed. Starting with the basic Markowitz model, several cardinal models are used to find optimum portfolios with select stock set. Having developed the regression model of t...

We examine the effects of trading and information flows on the short-run behavior of stock prices by comparing the behavior of stock return volatility during trading and nontrading periods. We define nontrading periods as periods when exchanges and businesses are open but traders endogenously choose not to trade. After correcting for the bid/ask bounce and stickiness in quotes, we find that a l...

We characterize the joint dynamics of expected returns, stochastic volatility, and prices. In particular, with a given dividend process, one of the processes of the expected return, the stock volatility, or the price-dividend ratio fully determines the other two. For example, the stock volatility determines the expected return and the price-dividend ratio. By parameterizing one, or more, of exp...

The main objective of this research is to optimize the stock portfolio of investment companies operating in the field of petrochemical and refining industries through minimizing risk with respect to the expected return. In this regard, first of all, the compositions of sample firm's portfolios were investigated during 2013 to 2016 and high-weight industries were selected. Then, the risk of retu...

I propose a new measure of common, time-varying tail risk for large cross sections of stock returns. Stock return tails are described by a power law in which the power law exponent is allowed to transition smoothly through time as a function of recent data. It is motivated by asset pricing theory and is estimable via quasi-maximum likelihood. Estimates indicate substantial time variation in sto...

This paper examines the hypothesis that both stock returns and volatility are asymmetrical functions of past information derived from domestic and US stock market news. By employing a double-threshold regression GARCH model to investigate four major index return series, we find significant evidence to sustain the asymmetrical hypothesis of stock returns. Specifically, evidence strongly supports...