Using data on identical and fraternal twins' complete financial portfolios, we decompose the cross-sectional variation in investor behavior. We find that a genetic factor explains about one third of the variance in stock market participation and asset allocation. Family environment has an effect...

Traditional finance explains individual investors' behavior and financial decision-making based on economic incentives and rationality. Modern finance, however, takes a holistic view and searches for not only economic but also biological, psychological, and social factors that shape...

We find that several factors explain an individual investor's style, i.e., the value versus growth orientation of the investor's stock portfolio. First, we find that an investor's style has a biological basis and is partially ingrained in an investor from birth. Second, we show that an...

We show that firm valuations fell after a key expense became more visible in financial statements. FAS 123-R required firms to deduct option compensation costs from earnings, instead of disclosing them only in footnotes. Firms that granted high option pay experienced a significant earnings...