Italy’s Non-Negligible Cohabitational Unions

Italy has long been regarded as the country with negligible non-marital cohabitation par excellence, but lately the pattern has begun to change and entry into consensual unions has increased strongly in younger Italian generations. This article is devoted to a study of such features between 1980 and 2003 based on the data from the Italian variant of the Gender and Generations Survey, Round 1. We consider entry into marriage and entry into cohabitation as competing risks and show how the incidence of cohabitation consistently much lower but has increased by some 70% over the 20-odd years of our study, while the marriage rate has dropped by almost as much. We find great variation across major regions of the country. The rise in cohabitation is confined to Northern and Central Italy, while the risk of marriage formation has declined strongly all over the country. Unlike previous investigations, our data suggest that non-marital cohabitation may be taking over whatever minor role civil marriage has had in Italian union formation.     

A non-linear time series approach to modelling asymmetry in stock market indexes

In this paper we analyse the performances of a novel approach to modelling non-linear conditionally heteroscedastic time series characterised by asymmetries in both the conditional mean and variance. This is based on the combination of a TAR model for the conditional mean with a Constrained Changing Parameters Volatility (CPV-C) model for the conditional variance. Empirical results are given for the daily returns of the S&P 500, NASDAQ composite and FTSE 100 stock market indexes.     

Measuring cross-country technological catch-up through variable-parameter FDH

In this paper, we estimate indices of technological catch-up for a sample of 52 countries through the FDH approach with variable scaling parameters proposed in Kerstens and Vanden Eeckaut (1999). We show that this technique has significant advantages for the international comparisons of productivity and, more generally, wherever the assumption of convexity for the production set is not likely to be appropriate. We want to thank Laurens Cherchye, Hal Fried, Kristian Kerstens and an anonymous referee for useful comments on preceding versions of this paper. The usual disclaimer applies. Financial support from the MURST, Italy, is gratefully acknowledged.     

The Input Evaluation of Generalized Bernoulli Processes for Salary Lines Construction by Means of Continuous Time Generalized Non-Homogeneous Semi-Markov Processes

Salary line forecasting assumes a relevant role in manpower and in pension funds Previously, the authors presented a generalized Bernoulli process, useful for forecasting the evolution of salary lines, taking into account the salary costs, the number of workers at each rank and the probability transitions between the ranks. The problem with applying this model is constructing the probability of transition between the grades. In this article, we will present a model that allows obtaining these probabilities by means of the solution of the evolution equation of a generalization of continuous time non-homogeneous semi-Markov processes.     

Wild bootstrap seasonal unit root tests for time series with periodic nonstationary volatility

We investigate the behavior of the well-known Hylleberg, Engle, Granger and Yoo (HEGY) regression-based seasonal unit root tests in cases where the driving shocks can display periodic nonstationary volatility and conditional heteroskedasticity. Our set up allows for periodic heteroskedasticity, nonstationary volatility and (seasonal) generalized autoregressive-conditional heteroskedasticity as special cases. We show that the limiting null distributions of the HEGY tests depend, in general, on nuisance parameters which derive from the underlying volatility process. Monte Carlo simulations show that the standard HEGY tests can be substantially oversized in the presence of such effects. As a consequence, we propose wild bootstrap implementations of the HEGY tests. Two possible wild bootstrap resampling schemes are discussed, both of which are shown to deliver asymptotically pivotal inference under our general conditions on the shocks. Simulation evidence is presented which suggests that our proposed bootstrap tests perform well in practice, largely correcting the size problems seen with the standard HEGY tests even under extreme patterns of heteroskedasticity, yet not losing finite sample relative to the standard HEGY tests.     

Probabilistic spatial power indexes

In this study, we present a generalization of spatial power indexes able to overcome their main limitations, namely (i) the excessive concentration of power measures; (ii) the too high sensitivity to players’ location in the ideological space. Voters’ propensity to support an issue is modeled via a random utility function with two additive terms: the deterministic term accounts for voters’ preference-driven/predictable behavior; the random one is a catch-all term that accounts for all the idiosyncratic/unpredictable factors. The relative strength of the two terms gives rise to a continuum of cases ranging from the Shapley value, where all aggregation patterns are equally probable, to a standard spatial value, like the Owen–Shapley index, where instead the conditional order is fully deterministic. As an illustrative application, we analyze the distribution of power in the Council of Ministers under three different scenarios: (i) EU15 Pre-Nice; (ii) EU27 Nice Treaty; (iii) EU27 Lisbon Treaty.     

Effects of tadalafil treatment combined with physical activity in patients with low onset hypogonadism: results from a not-randomized single arm phase 2 study

Purpose: To investigate a possible relation between penile Doppler ultrasound examination (PDUE) parameters and efficacy of chronic therapy with tadalafil (TAD) combined with a protocol of aerobic physical activity (PA) in patients with late onset hypogonadism (LOH). Methods: The study evaluated 30 patients consecutively enrolled with LOH and erectile dysfunction which present contraindication to hormonal replacement therapy for concomitant prostate disease. These patients were subjected to a combined protocol with phosphodiesterase V selective inhibitors (TAD 5?mg daily) and aerobic PA.

Results: After three months, we observed significant improvements in erectile function [IIEF-5, median (IQR)?=?13.0 (7.0–18.0) versus 6.0 (5.0–6.75); p?p?Conclusion: PA in association with phosphodiesterase V inhibitors could compensate the effects of hypogonadism on erectile function and facilitate the clinical response to these drugs even in the absence of adequate serum concentrations of total testosterone.     

Unit Root Tests under Time-Varying Variances

The paper provides a general framework for investigating the effects of permanent changes in the variance of the errors of an autoregressive process on unit root tests. Such a framework - which is based on a novel asymptotic theory for integrated and near integrated processes with heteroskedastic errors - allows to evaluate how the variance dynamics affect the size and the power function of unit root tests. Contrary to previous studies, it is shown that non-constant variances can both inflate and deflate the rejection frequency of the commonly used unit root tests, both under the null and under the alternative, with early negative and late positive variance changes having the strongest impact on size and power. It is also shown that shifts smoothed across the sample have smaller impacts than shifts occurring as a single abrupt jump, while periodic variances have a negligible effect even when a small number of cycles take place over a given sample. Finally, it is proved that the locally best invariant (LBI) test of a unit root against level stationarity is robust to heteroskedasticity of any form under the null hypothesis.     

Correlates of internal audit function involvement in sustainability audits

Journal of Management and Governance - While an increasing number of organizations are engaging in sustainability activities, assurance of these activities is relatively new. We investigate the...