On the law of one price

We consider the standard discrete-time model of a frictionless financial market and show that the law of one price holds if and only if there exists a martingale density process with strictly positive initial value. In contrast to the classical no-arbitrage criteria, this density process may change its sign. We also give an application to the CAPM.Received: November 2003, Mathematics Subject Classification (2000): 60G44JEL Classification: G13, G11Freddy Delbaen: This research was done during the stay of the author at Université de Franche-Comté.     

Precautionary saving in the presence of other risks

Does the sign of the third derivative of the utility function with respect to wealth still govern precautionary saving motives in the presence of a background risk? This article shows that some other properties of the utility function have also to be considered depending on the serial correlation existing between the background risk and the future income risk.     

Do Leveraged Firms Underinvest in Corporate Social Responsibility? Evidence from Health and Safety Programs in U.S. Firms

The explosion of health-related costs in U.S. firms over more than a decade is a huge concern for managers. The initiation of Health and Safety (H&;S) programs at the firm level is an adequate Corporate Social Responsibility (CSR) initiative to contain this evolution. However, in spite of their documented efficiency, firms underinvest in those programs. This appears as a puzzle for health economists. In this paper, we uncover a strong negative relation of financial leverage to the implementation of H&;S programs. The negative impact of debt on investment and CSR activities is generally interpreted as an efficient disciplinary effect of debt on managers. H&;S are particularly well suited to revisit this evidence, given their strong profitability and homogeneity across firms. Very interestingly, the negative effect is stronger for firms with high free cash flows, for which debt is used to prevent overinvestment. This strongly suggests that debt, while disciplining managers, also discourages investments which are valuable both for firms and society.     

Return to work after cancer and pre-cancer job dissatisfaction

We investigate the association between pre-cancer job dissatisfaction and return-to-work probability 3 years after a cancer diagnosis. We use a Danish data set combining administrative data and a survey to breast and colon cancer survivors. We find that the return-to-work probability has a negative correlation with pre-cancer job dissatisfaction with mental demands (where the correlation is driven by the high-educated) and with physical demands and the superior (where the correlation is driven by the low-educated). Educational gradients in the probability of returning to work after cancer are not significantly affected by controlling for pre-cancer job dissatisfaction and pre-cancer ability to work.     

Private Labels,National Brands and Food Prices

We study the relationships between national brand prices and the development of private labels, using home-scanned data from a consumer survey reporting purchases for 218 food products. When the impact of private label development is significant (116 cases out of 218), we observe a positive correlation (89%) between brand price and purchases of private labels. When controlling for changes in product quality, we still find a positive relation between private label development and national brand prices. Thus, the change in the national brand product characteristics only partly explains the increase in the national brand prices. Furthermore, the price reactions of national brands differ according to the type of private labels they face. Finally, we demonstrate that the development of private labels has less effect on the prices of second-tier brands than on the prices of the leading brand.      

Syndicated loans in emerging markets

There has been a considerable expansion of the volume of syndicated loans in emerging markets in the recent years. We provide the first analysis of the determinants of the decision of banks to syndicate a loan on a sample of loan facilities from 50 emerging countries. We show the significant role of loan characteristics and of financial development, banking regulation, and legal institutions, in the decision to syndicate a loan. We support the efforts of authorities to increase banking competition and efficiency, and to implement binding banking regulation on capital requirement to promote the expansion of syndicated loans.     

Institutional Reform and Co-Decision in the European Union

This paper studies the Treaty of Amsterdam's reform of the co-decision procedure in the European Union. The paper presents spatial models of the procedure, and examines whether the Treaty significantly alters it. The theory analyzes the implications of the Treaty for the equilibrium EU policies and the institutions' powers. It characterizes sets of policies the Commission can successfully propose under the old procedure, and sets of policies the Council and the Parliament can successfully propose as joint texts under the new procedure. The paper concludes that the new procedure does not lead to a further increase in the Parliament's powers, as intended by the drafters of the Treaty. Rather it finds that the Treaty eliminates the Commission's power under co-decision and may increase indecision.     

Storage and Viability of a Fishery with Resource and Market Dephased Seasonalities

In this study we analyse the role of the storageregulation in a fishery's production process when theresource exploited and the market to which theproduction is exported are characterized by seasonaldephased oscillations. For this purpose we built up adynamic model drawn from the French Guyana shrimpfishery example. The underlying objective of the modelis not the maximisation of a given criterion (as wouldbe in the optimal control approach), but merely themaintenance of the fishery's economical viability. Thefundamental principle is here to try to preserve asmany as possible viable control options. Theconditions to achieve and maintain this viability arecaptured in a certain number of constraints. Theanalysis points out periods and situations within theseason where the fishermen must anticipate theevolution of their storage to avoid violating thoseviability constraints. The study also indicates howthe fishery's viability can be ensured even if theexploitation costs exceed the commercial value of thelandings for a finite part of the year. However, whenthe resource's and/or market's oscillations are toolarge, the fishery may be not viable any longer and itappears that the crisis can not be removed byinvesting in larger storage capacities.     

Passive Hedge Fund Replication – Beyond the Linear Case

In this paper we extend Hasanhodzic and Lo (2007) by assessing the out‐of‐sample performance of various non‐linear and conditional hedge fund replication models. We find that going beyond the linear case does not necessarily enhance the replication power. On the other hand, we find that selecting factors on the basis on an economic analysis allows for a substantial improvement in out‐of‐sample replication quality, whatever the underlying form of the factor model. Overall, we confirm the findings in Hasanhodzic and Lo (2007) that the performance of the replicating strategies is systematically inferior to that of the actual hedge funds.     

Diversification and Value-at-Risk

A pervasive and puzzling feature of banks’ Value-at-Risk (VaR) is its abnormally high level, which leads to excessive regulatory capital. A possible explanation for the tendency of commercial banks to overstate their VaR is that they incompletely account for the diversification effect among broad risk categories (e.g., equity, interest rate, commodity, credit spread, and foreign exchange). By underestimating the diversification effect, bank’s proprietary VaR models produce overly prudent market risk assessments. In this paper, we examine empirically the validity of this hypothesis using actual VaR data from major US commercial banks. In contrast to the VaR diversification hypothesis, we find that US banks show no sign of systematic underestimation of the diversification effect. In particular, diversification effects used by banks is very close to (and quite often larger than) our empirical diversification estimates. A direct implication of this finding is that individual VaRs for each broad risk category, just like aggregate VaRs, are biased risk assessments.