Stock Market Participation Costs Research Articles

The impact of health insurance on stockholding: A regression discontinuity approach

Economic theory predicts that a reduction in background risk should induce financial risk-taking, particularly for individuals with low stock market participation costs. Hence, health insurance coverage could affect financial risk-taking by offsetting health-related background risk. We use a regression discontinuity design to examine whether Medicare eligibility at age 65 increases stockholding in the US and find that it does so for those with college education, but not for their less-educated counterparts who face higher stock market participation costs. Our results are unlikely due to the reduction of medical expenses associated with Medicare coverage because the latter does not affect bondholding.

The Impact of Health Insurance on Stockholding: A Regression Discontinuity Approach

Using data from the US Health and Retirement Study, we study the causal effect of increased health insurance coverage through Medicare and the associated reduction in health-related background risk on financial risk-taking. Given the onset of Medicare at age 65, we identify our effect of interest using a regression discontinuity approach. We find that getting Medicare coverage induces stockholding for those with at least some college education, but not for their less-educated counterparts. Hence, our results indicate that a reduction in background risk induces financial risk-taking in individuals for whom informational and pecuniary stock market participation costs are relatively low.

The Impact of Health Insurance on Stockholding: A Regression Discontinuity Approach

Using data from the US Health and Retirement Study, we study the causal effect of increased health insurance coverage through Medicare and the associated reduction in health-related background risk on financial risk-taking. Given the onset of Medicare at age 65, we identify our effect of interest using a regression discontinuity approach. We find that getting Medicare coverage induces stockholding for those with at least some college education, but not for their less-educated counterparts. Hence, our results indicate that a reduction in background risk induces financial risk-taking in individuals for whom informational and pecuniary stock market participation costs are relatively low.

Structural estimation of stock market participation costs

This paper develops and estimates a dynamic model of stock market participation, where consumers' decisions regarding stock market participation are influenced by participation costs. The practical significance of the participation costs is considered as being a channel through which financial education programs can affect consumers' investment decisions. Using household data from the Panel Study of Income Dynamics, I estimate the magnitude of the participation cost, allowing for individual heterogeneity in it. The results show the average stock market participation cost is about 4–6% of labor income; however, it varies substantially over consumers' life. The model successfully predicts the level of the observed participation rate and the increasing pattern of stock market participation over the consumers' life cycle.

Nature or nurture: What determines investor behavior?

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 on the behavior of young individuals, but this effect is not long-lasting and disappears as an individual gains experience. Frequent contact among twins results in similar investment behavior beyond a genetic factor. Twins who grew up in different environments still display similar investment behavior. Our interpretation of a genetic component of the decision to invest in the stock market is that there are innate differences in factors affecting effective stock market participation costs. We attribute the genetic component of asset allocation—the relative amount invested in equities and the portfolio volatility—to genetic variation in risk preferences.

Nature or Nurture: What Determines Investor Behavior?

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 on the behavior of young individuals, but this effect is not long-lasting and disappears as an individual gains experiences. Frequent contact among twins results in similar investment behavior beyond a genetic factor. Twins who grew up in different environments still display similar investment behavior. Our interpretation of a genetic component of the decision to invest in the stock market is that there are innate differences in factors affecting effective stock market participation costs. We attribute the genetic component of asset allocation - the relative amount invested in equities and the portfolio volatility - to genetic variation in risk preferences.

Information vs. Entry Costs: What Explains U.S. Stock Market Evolution?

AbstractI investigate whether changes in stock market participation costs can explain the long-term increase in the number of U.S. stockholders. I separate these costs into two components: an information cost (the cost of collecting market information), and an entry cost (all other costs, including commissions and fees), and disentangle their general equilibrium implications in a noisy rational expectations economy. While a falling information cost cannot explain the observed increase in stock market participation, a falling entry cost can account for this plus several other features of the U.S. economy, including the falling equity premium, rising return variances, and the boom in passive relative to active investing.

Occupational choice and the private equity premium puzzle

This paper suggests a resolution to what has come to be known as the ‘private equity premium puzzle’ (Am. Econom. Rev. 92(4) (2002) 745–778). We interpret occupational choice as a dynamic portfolio choice problem of a life-cycle investor facing a borrowing constraint, stock market participation costs and imperfect information about the profitability of potential businesses. Information is imperfect, because only entrepreneurs observe their own business risk realizations and there is a fixed cost of starting a business. Using numerical techniques we find that the model generates the empirically observed return structure for private and public equity with standard CRRA-preferences and fully rational expectations.

Awareness and Stock Market Participation

The paper documents lack of awareness of financial assets in the 1995 and 1998 Bank of Italy Surveys of Household Income and Wealth. It then explores the determinants of awareness, and finds that the probability that survey respondents are aware of stocks, mutual funds and investment accounts is positively correlated with education, household resources, long-term bank relations and proxies for social interaction. Lack of financial awareness has important implications for understanding the stockholding puzzle and for estimating stock market participation costs.

Portfolio choice with internal habit formation: a life-cycle model with uninsurable labor income risk

Motivated by the success of internal habit formation preferences in explaining asset pricing puzzles, we introduce these preferences in a life-cycle model of consumption and portfolio choice with liquidity constraints, undiversifiable labor income risk and stock-market participation costs. In contrast to the initial motivation, we find that the model is not able to simultaneously match two very important stylized facts: a low stock market participation rate, and moderate equity holdings for those households that do invest in stocks. Habit formation increases wealth accumulation because the intertemporal consumption smoothing motive is stronger. As a result, households start participating in the stock market very early in life, and invest their portfolios almost fully in stocks. Therefore, we conclude that, with respect to its ability to match the empirical evidence on asset allocation behavior, the internal habit formation model is dominated by its time-separable utility counterpart.

Portfolio Choice with Internal Habit Formation: A Life-Cycle Model with Uninsurable Labor Income Risk

Motivated by the success of internal habit formation preferences in explaining asset pricing puzzles, we introduce these preferences in a life-cycle model of consumption and portfolio choice with liquidity constraints, undiversifiable labor income risk and stock-market participation costs. In contrast to the initial motivation, we find that the model is not able to simultaneously match two very important stylized facts: A low stock market participation rate, and moderate equity holdings for those households that do invest in stocks. Habit formation increases wealth accumulation because the intertemporal consumption smoothing motive is stronger. As a result, households start participating in the stock market very early in life, and invest their portfolios almost fully in stocks. Therefore, we conclude that, with respect to its ability to match the empirical evidence on asset allocation behavior, the internal habit formation model is dominated by its time-separable utility counterpart.

Learning Under Ambiguity

This paper considers learning when the distinction between risk and ambiguity (Knightian uncertainty) matters. Working within the framework of recursive multiple-priors utility, the paper formulates a counterpart of the Bayesian model of learning about an uncertain parameter from conditionally i.i.d. signals. Ambiguous signals capture differences in information quality that cannot be captured by noisy signals. They may increase the volatility of conditional actions and they prevent ambiguity from vanishing in the limit. Properties of the model are illustrated with two applications. First, in a dynamic portfolio choice model, stock market participation costs arise endogenously from preferences and depend on past market performance. Second, ambiguous news induce negative skewness of asset returns and may increase price volatility. Shocks that trigger a period of ambiguous news induce a price discount on impact and are likely to be followed by further negative price changes.

Life-Cycle Asset Allocation: A Model with Borrowing Constraints, Uninsurable Labor Income Risk and Stock-Market Participation Costs

We study life-cycle asset allocation in the presence of liquidity constraints and undiversifiable labor income risk. The model includes three different assets (cash, long-term government bonds and stocks) and it takes into account the life-cycle profile of housing expenditures. With a modest correlation between stock returns and earnings innovations, the mean share of wealth invested in stocks never exceeds 45% during working-life. Moreover, the combination of uninsurable human capital and borrowing constraints rationalizes the asset allocation puzzle of Canner, Mankiw and Weil (1997). Nevertheless we argue that asset allocation models must match another important feature of the data: a low stock market participation rate. Along this dimension the model provides a very modest improvement, still predicting a counterfactually high participation rate. We show that this arises from the link between risk aversion and prudence, implying that explanations for the participation puzzle based on the role of background risk are unlikely to succeed.