A note on risk aversion and herd behavior in financial markets

We show that differences in market participants risk aversion can generate herd behavior in stock markets where assets are traded sequentially. This in turn prevents learning of market’s fundamentals. These results are obtained without introducing multidimensional uncertainty or transaction cost. JEL Classification G1 · G14 · C11 · D82     

Estimating Risk Attitudes in Denmark: A Field Experiment*

We estimate individual risk attitudes using controlled experiments in the field in Denmark. The experiments were carried out across Denmark using a representative sample of 253 people between 19 and 75 years of age. Risk attitudes are estimated for various individuals differentiated by socio‐demographic characteristics. Our results indicate that the average Dane is risk averse, and that risk neutrality is an inappropriate assumption to apply. We also find that risk attitudes vary significantly with respect to several important socio‐demographic variables such as age and education. However, we do not find any effect of sex on risk attitudes.     

The Effect of Managerial Incentives to Bear Risk on Corporate Capital Structure and R&D Investment

In this study we use estimates of the sensitivities of managers' portfolios to stock return volatility and stock price to directly test the relationship between managerial incentives to bear risk and two important corporate decisions. We find that as the sensitivity of managers' stock option portfolios to stock return volatility increases firms tend to choose higher debt ratios and make higher levels of R&D investment. These results are even stronger in a subsample of firms with relatively low outside monitoring. For these firms, managerial incentives to bear risk play a particularly pivotal role in determining leverage and R&D investment.     

A new interpretation for the precautionary saving motive: a note

This paper proposes a new interpretation for the precautionary saving motive: when future income is uncertain, agents increase saving in order to cause a reduction in the disutility due to uncertainty. Furthermore, the paper shows that the usual necessary and sufficient condition for precautionary saving is the condition ensuring this effect to occur and gives new insights into the relationship between risk aversion indexes and precautionary saving.      

Optimal exercise of executive stock options

Valuing executive stock options is a challenging problem, because the standard risk-neutral valuation of those options is not appropriate; the executive is not allowed to trade the stock of the firm, so is not operating in a complete market. As this paper shows, an executive holding many American-style call options on his firm’s stock will optimally exercise the options bit by bit, whereas a risk-neutral valuation of the options would assume that all are exercised at the same time. Comparative statics of the optimal exercise policy show many surprising features.      

Price Stabilization and the Risk-Averse Firm

An analytically simple and tractable approach to firm-level welfare analysis of complete and partial mean-preserving price stabilization for producers with general risk-averse preferences facing a stochastic technology is developed. Necessary and sufficient conditions for price stabilization to be welfare enhancing are derived under different assumptions of the producer's preferences and the producer's technology. Existing stabilization results for the risk-averse firm are shown to be corollaries of these more general results.     

MONOTONICITY PROPERTIES OF OPTIMAL INVESTMENT STRATEGIES FOR LOG-BROWNIAN ASSET PRICES

Consider the geometric Brownian motion market model and an investor who strives to maximize expected utility from terminal wealth. If the investor's relative risk aversion is an increasing function of wealth, the main result in this paper proves that the optimal demand in terms of the total wealth invested in a given risky portfolio at any date is decreasing in absolute value with wealth. The proof depends on the functional form of the Brunn–Minkowski inequality due to Prékopa.     

Trust and trustworthiness across different age groups

We examine the degree of trust and trustworthiness in an experimental trust game with 662 participants from six different age groups, ranging from 8-year-olds to retired persons. Although both trust and trustworthiness have been identified as fundamental pillars for efficient economic interactions, economic research has devoted little attention to measuring their strength in different age groups. In our experiment subjects interact with members of the same age group. We find that trust increases almost linearly from early childhood to early adulthood, but stays rather constant within different adult age groups. Trustworthiness prevails in all age groups.     

From sure to strong diversification

This paper presents a characterization of weak risk aversion in terms of preference for sure diversification. Similarly, we show that strong risk aversion can be characterized by weakening preference for diversification,as introduced by Dekel (Econometrica 57:163,1989), in what we call preference for strong diversification. We are grateful to Jean-Yves Jaffray, Peter Wakker and anonymous reference for very helpful suggestions and comments.     

Bank Mergers and Diversification: Implications for Competition Policy

This paper analyses competition and mergers among risk averse banks. We show that the correlation between the shocks to the demand for loans and the shocks to the supply of deposits induces a strategic interdependence between the two sides of the market. We characterise the role of diversification as a motive for bank mergers and analyse the consequences of mergers on loan and deposit rates. When the value of diversification is sufficiently strong, bank mergers generate an increase in the welfare of borrowers and depositors. If depositors have more correlated shocks than borrowers, bank mergers are relatively worse for depositors than for borrowers.