We integrate appealing features of Markowitz’s mean-variance portfolio theory (MVT) and Shefrin and Statman’s behavioral portfolio theory (BPT) into a new mental accounting (MA) framework. Features of the MA framework include an MA structure of portfolios, a definition of risk as the...

We integrate appealing features of Markowitz's mean-variance portfolio theory (MVT) and Shefrin and Statman's behavioral portfolio theory (BPT) into a new mental accounting (MA) framework. Features of the MA framework include a mental accounting structure of portfolios, a definition of risk as...

While correlation is the common indicator of the benefits of diversification, it is not a good indicator. This is for three reasons. First, diversifiable risk depends not only on the correlations between stock returns but also on the standard deviations of stock returns. Second, correlation does...

Correlations between the returns of U.S. stocks and international stocks were higher recently than in the past, reaching 0.86 during the 60 months ending in December 2003. Today's investors note the high correlations between U.S. and international stocks and doubt the benefits of global...

Correlation is the common measure of the benefits of diversification, but dispersion, measured as the standard deviation of the returns of stocks around the mean of all stocks, is better. This is for two reasons. First, the benefits of diversification depend not only on the correlations between...

The price of Berkshire Hathaway shares increased at a rate more than double the rate of the Samp;P 500 Index, from $18 on May 10, 1965, when Warren Buffett took control of the company, to $71,000 by the end of 2000. We show that while some investors saw Berkshire Hathaway?s amazing performance...

Correlation is the common indicator for the benefits of diversification, but it is not a good indicator. This is for two reasons. First, the benefits of diversification depend not only on the correlations between returns but also on the standard deviations of returns. Second, correlation does...

Correlations between the returns of US stocks and international stocks were higher recently than in the past, reaching 0.86 during the 60 months ending in December 2003. Today's investors note the high correlations between US and international stocks and doubt the benefits of global...