Martingale applicate alla teoria del rischio: Processi di guadagno a submartingala e aggiustabilità

Viene formalizzata e studiata l'attività di una compagnia che opera in un mercato assicurativo non vita. Si ipotizza che il guadagno realizzato sulla generica polizza sia una submartingala. Si danno disuguaglianze significative per la probabilità di rovina all'infinito ed entro l'n-mo periodo nel caso in cui il rendimento di portafoglio della compagnia sia “aggiustabile”. I risultati vengono discussi nel caso in cui il mercato sia stratificato in classi di rischio nell'ipotesi di indipendenza; si accenna al caso particolare di rischi poissoniani e all'ipotesi di correlazione interna alle classi di rischio.     

Convergence in per-capita GDP across European regions: a reappraisal

This paper studies convergence in per-capita GDP across European regions over the period 1980–2000. We use median unbiased estimators of the rate of convergence to the steady-state growth path, while allowing for unrestricted patterns of heterogeneity and spatial correlation across regions. By permitting the model parameters to be completely different across regions, not only we avoid imposing strong a priori assumptions but we are also able to analyze the spatial patterns in the estimated coefficients. Our results differ from those found using conventional estimators. The main differences are: i) the mean rate of convergence is much lower; ii) for most regions this rate is zero; iii) the number of regions for which we reject equality in trend growth rates is substantially lower. We also find significant evidence of correlation of growth rates across neighbor regions and across regions belonging to the same country.     

Fiscal discipline and flexibility in EMU: the implementation of the Stability and Growth Pact

Fiscal discipline to safeguard the credibility of the singlemonetary authority and fiscal flexibility to respond to country-specificshocks are two core principles governing budgetary policy inEMU. The Stability and Growth Pact aims at ensuring the firstobjective. To comply with the requirements of the pact, EU membersneed to achieve a 'close to balance or surplus' position andchange their budgetary behaviour in periods of cyclical upturnsby refraining from spending the 'growth dividend'. Past experienceshows that fiscal laxity does not buy more effective stabilization.Once EMU countries have achieved their medium-term target, theirautomatic stabilizers will be able to operate fully, thus helpingin smoothing out cyclical fluctuations. The main potential problemsin the implementation of the pact may arise in the early yearsof EMU, during the transition to a balanced budget, in the eventof a slow-down in economic activity.     

Peer choice in CEO compensation

Current research shows that firms are more likely to benchmark against peers that pay their Chief Executive Officers (CEOs) higher compensation, reflecting self serving behavior. We propose an alternative explanation: the choice of highly paid peers represents a reward for unobserved CEO talent. We test this hypothesis by decomposing the effect of peer selection into talent and self serving components. Consistent with our prediction, we find that the association between a firm's selection of highly paid peers and CEO pay mostly represents compensation for CEO talent.     

Heterogeneity in health responses and anchoring vignettes

In this article we employ the tool of anchoring vignettes to analyze gender differences in self-assessments of health in Europe. We propose and estimate an extension of the basic vignette model for correcting the lack of interpersonal comparability of self-assessments on a categorical scale. Our extension allows for potential correlation in the self-assessments of health on different domains by including an unobservable individual effect, common to all domains but different across individuals, in both the thresholds and the equations for the latent health problems. After applying this model to the SHARE data, we find that vignettes help narrow gender differences in self-assessments of health, although these differences are not entirely eliminated.     

Efficiency and risk in European banking

We assess the inter-temporal relationship between bank efficiency, capital and risk in a sample of European commercial banks employing several definitions of efficiency, risk and capital and using the Granger-causality methodology in a panel data framework. Our results suggest that lower bank efficiency with respect to costs and revenues Granger-causes higher bank risk and that increases in bank capital precede cost efficiency improvements. We also find that more efficient banks eventually become better capitalized and that higher capital levels tend to have a positive effect on efficiency levels. These results are generally confirmed by a series of robustness tests. The results have potentially important implications for bank prudential supervision and underline the importance of attaining long-term efficiency gains to support financial stability objectives.     

Academic spin-off creation: barriers and how to overcome them

The aim of this study is to analyze the process of academic spin-off creation, identifying the barriers to suggest how to overcome them. For this purpose, a case study method was adopted, and as data-collecting instruments, several in-depth interviews and documentary analysis were used from three academic spin-offs. The empirical evidence captures the different views of the founding researchers of the academic spin-offs, the researching lecturers in the department creating the spin-offs and the manager of the technology transfer office at the Portuguese university studied here. The results show that the different perceptions of barriers are seen to be solved through an internal strategy within the university. The findings also show that applied research should be valued in assessing lecturers, as it contributes, not only to the link with industry, and therefore to regional development, but also to universities' sustainability, overcoming the lack of financial support as a result of constant budget cuts. The contact networks resulting from universities' links with the different stakeholders will benefit the spin-offs themselves, facilitating their survival in the first years of their life.