Analysis of the Covariance Structure in Manufactured Parts

We discuss the use of variograms for covariance modeling under the Kriging model to assess tolerances on manufactured parts. The variogram is very informative about the spatial dependence and it is favored by researchers in the choice of a correlation function. It may give evidence of anisotropy and of nugget effect too. In this paper, various variogram estimators from literature are used for comparing and evaluating their properties in assessing the surface error of three workpieces manufactured with different machining precisions. Contrary to the common engineering belief, the variograms give evidence of both technological signatures and systematic errors of the measurement machines.     

DEA-Like Model and Common Weights Approach for the Construction of a Subjective Community Well-Being Indicator

A growing literature assesses the quality of life and well-being in geographically and/or politically divided areas. The paper proposes a new subjective well being (SWB) indicator based on residents’ satisfaction with environment and community, personal life and leisure activities. Our approach is a novel construction and new application of the well-being index, specifically, a DEA-like model with common weights under the benefit of the doubt (BoD) approach. This approach is very interesting in the SWB framework, allowing us to differentiate efficient individuals or estimate the relative importance of each domain in the SWB indicator. The results state that Personal life is the domain that most profoundly affects SWB index; it also differs in groups of individuals and geographic spaces.     

Least Squares Sparse Principal Component Analysis: A Backward Elimination Approach to Attain Large Loadings

Sparse principal components analysis (SPCA) is a technique for finding principal components with a small number of non‐zero loadings. Our contribution to this methodology is twofold. First we derive the sparse solutions that minimise the least squares criterion subject to sparsity requirements. Second, recognising that sparsity is not the only requirement for achieving simplicity, we suggest a backward elimination algorithm that computes sparse solutions with large loadings. This algorithm can be run without specifying the number of non‐zero loadings in advance. It is also possible to impose the requirement that a minimum amount of variance be explained by the components. We give thorough comparisons with existing SPCA methods and present several examples using real datasets.     

Modified first-difference estimator in a panel data model with unobservable factors both in the errors and the regressors when the time dimension is small

Panel data models with factor structures in both the errors and the regressors have received considerable attention recently. In these models, the errors and the regressors are correlated and the standard estimators are inconsistent. This paper shows that, for such models, a modified first-difference estimator (in which the time and the cross-sectional dimensions are interchanged) is consistent as the cross-sectional dimension grows but the time dimension is small. Although the estimator has a non standard asymptotic distribution, t and F tests have standard asymptotic distribution under the null hypothesis.     

The Italian Regional Well-Being in a Multi-expert Non-additive Perspective

This paper designs a multidimensional index of well-being for 20 Italian regions, based on a set of 41 indicators organized in an original hierarchical structure, a decision-tree whose four main pillars are Economy, Society, Environment and Health. Our novel approach combines the objective dimension of the evaluation (a comprehensive set of statistical indicators) within a flexible non-additive aggregation model (the Choquet integral) characterized with the preferences of informed Italian stakeholders. Adopting the Choquet integral allows us to overcome the well-known limitations embedded in the linear models, by assigning a weight (capacity) to any coalitions of dimensions, and by allowing a different degree of substitutability within each decision node in the tree. The weights and the parameters for the aggregation are elicited through a computer-based nominal group technique, a method which reduces the occurrences of drastically dissenting valuations and the potential expert-selection bias. Our results show that experts’ perception of synergies and redundancies is quite heterogeneous between levels and nodes in the tree. Moreover, well-being measures are much influenced by the degree of substitutability embedded in the experts’ preferences. Overall, the Italian picture looks more heterogeneous when analysed through the Choquet integral, with respect to a linear model.     

‘That right level of intoxication’: A Grounded Theory study on young adults’ drinking in nightlife settings

The present study examined the meaning and functions of drinking across different nightlife settings (e.g., bars, dance clubs) in a sample of Italian young adults. A Grounded Theory recursive and iterative process of data collection, through 10 focus group interviews, and data analysis revealed the complex and dynamic nature of young people's experience of drinking in nightlife settings. Results indicated that three major categories of social nightlife settings associated with different meanings and uses of alcohol: a more moderate social drinking in bars, a pursuit of a desired level of intoxication in dancing settings, like nightclubs, with festivities and celebratory settings most associated with alcohol abuse and heavy drunkenness as a mean to maximize the celebration and the uniqueness of the event. The core category emerging was related to the collective social process of youngsters optimizing alcohol intake throughout the night to find and maintain a desired level of intoxication (‘just the right buzz’) in dancing settings, to reach a controlled disinhibition to get what they consider positive outcomes minimizing negative ones. Results can be informative for other cultural regions too where differences in the drinking experience across nightlife settings have not been fully addressed yet.     

Valuing and Integrating Informal Care as a Core Component of Long-Term Care for Older People: A Comparison of Recent Developments in Italy and Spain

The international long-term care (LTC) debate has recently been focusing on how to strengthen home care provision. In this regard, a major role has been played by informal care and how to best integrate it in a holistic care approach. Italy and Spain, usually labeled as “familialist” or “family-based” care models, have been promoting national reforms or actions to support the integration of “informal” actors into the overall LTC system. Through a comparative review of recent trends observed in the two care regimes, this article aims at contributing to improve our cross-national understanding of how LTC is changing across Europe, identifying the basic approaches adopted in Italy and Spain and highlighting both their strengths and drawbacks.     

Epidemiology and risk factors of lower urinary tract symptoms/benign prostatic hyperplasia and erectile dysfunction

Benign prostatic hyperplasia (BPH) is very common in aging men and causes lower urinary tract symptoms (LUTS), which decrease health-related quality of life. A number of evidence suggests that other than ageing, modifiable factors, such as increasing prostate volume, obesity, diet, dyslipidemia, hormonal imbalance, hypertension, metabolic syndrome, alcohol, and smoking, also contribute to the development of BPH and/or LUTS. More recently, erectile dysfunction (ED) has been linked to LUTS/BPH as a part of this syndrome, suggesting that patients with BPH or LUTS easily develop ED, and that LUTS/BPH symptoms often coexist with ED. This article focuses on the epidemiology and risk factors of the combined phenotype LUTS/BPH – ED.