On a variational formulation used in credit risk modeling

We consider the credit risk model of Collin-Dufresne and Goldstein (2001). According to this model, the price of a defaultable bond can be efficiently computed using a variational formulation that consists of an integral relation and a Volterra integral equation. In Collin-Dufresne and Goldstein (2001) this integral equation is justified by a probabilistic intuition, but is not proven formally. In this paper we analytically derive the variational formulation used in Collin-Dufresne and Goldstein (2001). This analysis allows to give a correct characterization of the solution of the integral equation. Furthermore the approach proposed in this paper could also be employed for other models of credit risk.     

Financial globalization, financial crises and contagion

Two observations suggest that financial globalization played an important role in the recent financial crisis. First, more than half of the rise in net borrowing of the U.S. non-financial sectors since the mid-1980s has been financed by foreign lending. Second, the collapse of the U.S. housing and mortgage-backed-securities markets had worldwide effects on financial institutions and asset markets. Using an open-economy model where financial intermediaries play a central role, we show that financial integration leads to a sharp rise in net credit in the most financially developed country and to large asset price spillovers of country-specific shocks to bank capital. The impacts of these shocks on asset prices are amplified by bank capital requirements based on mark-to-market.     

Patents, Secrets, and the First-Inventor Defense

We analyze optimal patent design when innovators can rely on secrecy to protect their innovations. Secrecy has no fixed term but does not preclude accidental disclosure nor independent creation by other inventors. We derive the optimal scope of the rights conferred to such second inventors, showing that if the patent life is set optimally, second inventors should be allowed to patent and to exclude first inventors who have relied on secrecy. We then identify conditions under which it is socially desirable to increase patent life as much as is necessary to induce first inventors to patent. The circumstances in which it is preferable that they rely on secrecy seem rather limited .     

A signalling model of school grades under different evaluation systems

We examine the role of school grades as a signal of worker productivity under different examination systems in relation to errors that may affect student performance. Firms use school grades as a signal of workers’ effective skills, taking into account that these evaluations are effected by stochastic shocks. We show that more precise evaluation systems, being associated with a higher reactivity of wages to school grades, induce students to provide more effort. Low ability students tend to react less than high ability students. Moreover, individuals with low abilities may prefer less accurate evaluation systems. Nevertheless, when productivity increases, these systems become less convenient and the number of individuals preferring them diminishes. Our analysis highlights an important trade-off between centralised and decentralised evaluation systems. On the one hand, frequent evaluations, typical of decentralised systems, weaken the impact on grades of those errors which influence student performance and, so, reduce signal noise, while, on the other hand, different teachers generally adopt different performance assessment standards, leading to noisier evaluations.     

A Hausman-type test to detect the presence of influential outliers in regression analysis

In regression analysis, classical estimations may be excessively influenced by a few atypical observations. We propose a Hausman-type test to balance robustness and efficiency and to check whether a robust method should be implemented. An economic application is presented.     

The impact of fiscal-monetary policy interactions on government size and macroeconomic performance

This paper analyzes the relationship between inflation, output and government size by reexamining the time inconsistency of optimal monetary and fiscal policies in a general equilibrium model with staggered timing structure for the acquisition of nominal money à la Neiss (Neiss, Katharine S. (1999), Discretionary Inflation in a General Equilibrium Model, Journal of Money, Credit and Banking, 31(3), pp. 357–374.), and public expenditure financed by means of a distortive tax. It is shown that, with predetermined wages, the equilibrium rate of inflation is above the Friedman rule and the equilibrium tax rate is below the efficient level. In particular, the discretionary rate of inflation is nonmonotonically related to the natural output, positively related to government size, and negatively related to the degree of central bank conservatism. Finally, a regime with commitment leads to welfare improvements over a regime with discretion.     

A signaling model of environmental overcompliance

We present a theory of unilateral regulatory overcompliance as a signaling device. Firms that have a competitive advantage in the use of a cleaner but more costly technology overcomply in order to signal to an imperfectly informed, benevolent government that compliance costs are low, thereby triggering tougher regulation. We identify the conditions under which such an overcompliance signaling equilibrium arises, showing that there may be over-overcompliance in that firms may overcomply even when tougher regulation is not socially desirable. We also discuss the differential implications of the signaling theory as compared to other theories of unilateral regulatory overcompliance.     

Measuring ‘indirect’ investments in ICT in OECD countries

ABSTRACT

ICT components, such as microprocessors, may be embodied in other capital goods not recorded as ICT in National Accounts. We name ‘indirect ICT investment’ the value of embodied ICT components in non-ICT investment. The paper provides estimates of ‘indirect ICT investment’ based on detailed and unpublished Supply-Use tables (SUT) in 12 OECD countries: Australia, Belgium, Canada, Chile, Czech Republic, Denmark, France, Germany, Japan, Israel, Mexico, New Zealand, the United Kingdom, and the United States.

Our main finding is that ICT investment appears significantly higher when considering its indirect component, the average increase being about 35%. The inclusion of indirect ICT investment, excluding software (for which firms’ expenditures are difficult to measure), changes significantly the relative position of countries with respect to the ICT intensity of their investments. The inclusion of software further increases indirect ICT investment but the increase is smaller (in percentage) than without this inclusion. A final result, but concerning only three countries, it that the diagnosis of a stabilisation, or even a decrease, of ICT investment in percentage of GDP or of total investment, observed from the beginning of the century, is not modified if we take into account the indirect ICT investment.