Testing the purchasing power parity through I(2) cointegration techniques

This paper contributes to the empirical literature on the purchasing power parity (PPP) over the post‐Bretton Woods period by providing a time‐series based interpretation of the controversial evidence characterizing the dynamics of real exchange rates. It is shown that the persistence of deviations from the PPP between a set of European countries and the United States may be empirically attributed to the presence of I(2) stochastic trends in prices using Consumer Price Indices. Interestingly, the slow adjustment towards the equilibrium can be modelled through ‘integral‐proportional’ equilibrium correction models and this evidence can be partly reconciled with theories where the inflation rate reduces the markup of profit‐maximizing firms acting on imperfectly competitive markets. Copyright © 2005 John Wiley & Sons, Ltd.     

A generalized approach to optimal hedging with option contracts

In this paper, we develop a theoretical model in which a firm hedges a spot position using options in the presence of both quantity (production) and basis risks. Our optimal hedge ratio is fairly general, in that the dependence structure is modeled through a copula function representing the quantiles of the hedged position, and hence any quantile risk measure can be employed. We study the sensitivity of the exercise price which minimizes the risk of the hedged portfolio to the relevant parameters, and we find that the subjective risk aversion of the firm does not play any role. The only trade-off is between the effectiveness and cost of the hedging strategy.     

What’s up after brain drain? Sometimes, somewhere, someone comes back: a general model of return migration

Individual preferences and wage differentials are generally interpreted as determinants of agents?? migration decisions in search of job opportunities. Literature about migration flows usually describes both theoretical and empirical evidence for either temporary or permanent movements of workers, but brain drain migration has its own peculiar characteristics. This paper aims to obtain two results: the first is to present the law of determination that leads to the moment of the return decision, and the second is to analyse how the difference between the utility from domestic and foreign consumption evolves in time. The presented model explains how the return decision is determined, even in cases when the agent does not leave or does not return at all.     

A note on the sensitivity analysis of the internal rate of return

In this note we discuss the sensitivity analysis of the internal rates of return (IRR). We show that the use of partial derivatives can be misleading in the identification of key drivers of an investment project's performance. To remedy this shortcoming, we propose the use of an alternative sensitivity measure called the Differential Importance Measure. The analysis shows that, even if the theoretical conditions for using the Net Present Value or the IRR as valuation criteria apply, the sensitivity analysis results for the two indicators may differ.     

International Knowledge Diffusion and Home‐bias Effect: Do USPTO and EPO Patent Citations Tell the Same Story?*

This paper estimates the international diffusion of technical knowledge using patent citations. We control for self‐citations and for procedural differences between patent offices using equivalent patents. We find that (1) there are clear biases in patent examination processes that generate citations in the two offices; (2) at the EPO there is a strong localization effect at the country level, and the size is comparable to that found at the USPTO; (3) technological fields have different properties of diffusion in the two patent offices that do not depend on a patent office bias; (4) using EPO data, the US is not the leading country in terms of citations made and received, as occurs at the USPTO.     

The role of time value in convertible bond call policy

Since the seminal work of Ingersoll (1977b) the optimal time in which a firm should redeem its outstanding convertible bonds has received large attention by the financial literature. Several studies have put forward a number of possible costs and benefits for a firm if it interrupts the life of its convertible bonds prior to their contractual maturity. However, in this paper we argue that the managerial decision to call back a convertible bond is mainly driven by a fundamental variable almost neglected up until now: the time value extraction from bondholders’ conversion option. Accordingly, we propose a measure for the effective convenience of calling—which we define as net time value advantage—and we show, using a survival analysis, that it is more effective than previously proposed measures in explaining the firms’ observed call policy.     

Regional convergence in Italy, 1891–2001: testing human and social capital

The article aims to present and discuss estimates of levels of human and social capital in Italy??s regions over the long term, i.e., roughly from the second half of the nineteenth century up to the present day. The results are linked to newly available evidence for regional value added in order to begin to form an explanatory hypothesis of long-term regional inequality in Italy: convergence in value added per capita is tested in light of the neoclassical exogenous growth approach, which incorporates human capital and social capital as conditioning variables into a long-term production function. In contrast with conventional wisdom (e.g. Putnam 1993), we find that social capital was not a significant predictor of economic growth in post-Unification Italy: It grew in importance only in the last decades. Conversely, human capital was more important in the first half of the twentieth century. Results suggest that there was not one single conditioning variable over the long run, thus supporting the view that, in different periods, conditioning variables can be determined by technological regimes.     

The externalisation of R&D activities and the growing market of product development services

Several authors in recent years have discussed the observed trend towards the externalisation of (part of) a firm's R&D activities. As a consequence, several companies have been created that provide innovators with technical and scientific services such as R&D contracts, laboratory testing services, technology consulting, industrial design, engineering.
The paper is based upon an empirical study which consists of (i) an extensive analysis, in which information has been collected (for about two hundred companies) on size, location and type of services offered; (ii) an intensive analysis, in which one case is studied in depth of a company providing product development services. Some conclusions have been drawn regarding the characteristics of the market of product development services and the management and organisation of companies operating in that market.     

帮助贫困人口

在贫困国家，用于教育与卫生保健的支出能促进人力资本的发展，并帮助它们实现千年发展目标，不过政府必须敢于承担责任。