Estimating the Effect of Perceived Risk of Crime on Social Trust in the Presence of Endogeneity Bias

This study aims to estimate the effect of perceived risk of crime on the social trust probability for Italian men and women, accounting for both observed and unobserved confounding. We use microdata collected by the Italian National Statistical Office for the year 2010 during a multi-scope survey of Italian households. The relationship under investigation is estimated after controlling for observed confounding by using a propensity score weighting approach. To control for both observed and unobserved confounding (better known as endogeneity), a semiparametric recursive bivariate probit approach is ultimately employed instead. Our findings show that the perceived risk of crime has a significant negative effect on the social trust probability regardless of gender and that endogeneity seems to be present for both genders. The paper represents the first such application in which the effect of interest is estimated accounting for the presence of endogeneity.     

Fertility-related pensions and cyclical instability

In this paper, we study a general equilibrium model with overlapping generations, endogenous fertility and public pensions. By assuming Cobb–Douglas technology and logarithmic preferences, we show that the introduction of a fertility-related component in the pay-as-you-go pension scheme may destabilise the long-term equilibrium and cause endogenous fluctuations when individuals have static expectations. The possibility of cyclical instability increases (resp. reduces) when both the subjective discount factor and relative weight of individual fertility in pay-as-you-go pensions (resp. the parents’ taste for children) increase(s). Interestingly, when public pensions are contingent on the individual number of children, the financing of small-sized benefits may cause the occurrence of a flip bifurcation, two-period cycles and cycles of a higher order. In addition, we show through numerical simulations that these results hold in a more general setting with a constant inter-temporal elasticity of substitution utility function and a constant elasticity of substitution production function. Our findings identify a possible novel factor responsible for persistent deterministic fluctuations in a context of overlapping generations, while also representing a policy warning regarding the destabilising effects of fertility-related pension reforms, which are currently high in both the theoretical debate and the political agendas of several developed countries.     

Ein Ansatz zur Förderung von Reflexionskompetenz: Fallarbeit in 7 Schritten

This article describes a didactical model for higher education purposes focusing on the development of theory driven and self driven ‘case reflection competence’. We (Telse Iwers-Stelljes and Renate Luca) have developed this procedure in the last 6 years and formative evaluated it in different investigations. Starting point of this project were the actual results on studies of antinomical conditions of professional teachers and students in the classroom environment and the intention to find a humanistic psychologically-oriented access to handle them. In the following, we are going to describe 1) the theoretical foundations of our researches to explain the context of our model, 2) its methodical implementation and 3) a case reconstruction based on an example reflected by one of our students.     

Improved inference on capture recapture models with behavioural effects

In the context of capture-recapture modeling for estimating the unknown size of a finite population it is often required a flexible framework for dealing with a behavioural response to trapping. Many alternative settings have been proposed in the literature to account for the variation of capture probability at each occasion depending on the previous capture history. Inference is typically carried out relying on the so-called conditional likelihood approach. We highlight that such approach may, with positive probability, lead to inferential pathologies such as unbounded estimates for the finite size of the population. The occurrence of such likelihood failures is characterized within a very general class of behavioural effect models. It is also pointed out that a fully Bayesian analysis overcomes the likelihood failure phenomenon. The overall improved performance of alternative Bayesian estimators is investigated under different non-informative prior distributions verifying their comparative merits with both simulated and real data.     

Framing socioecological complexity: The long-term evolution of multiple dimensions of desertification risk in Italy

Desertification risk depends on the interplay of biophysical and socioeconomic drivers, among which climate change, soil depletion, landscape modifications, and biodiversity decline are key factors of change in Southern Europe. The present study introduces a diachronic analysis of desertification risk in Italy adopting a multidimensional approach based on four dimensions (ecological, economic, demographic, and administrative) assessed at three dates (1961, 1991, and 2011). These risk components were evaluated separately in Southern Italy, a formerly affected region (sensu United Nations Convention to Combat Desertification), and Northern/Central Italy, a nonaffected region in the country. All risk measures document how the divide between affected and nonaffected regions in Italy has gradually reduced. Because of local warming and rising human pressure, Northern Italy has recently displayed a level of desertification risk close to those observed in Southern Italy over the last 30 years. These results suggest a thorough revision of the national classification of risky areas, that may inform more specific mitigation and adaptation policies responding effectively to recent socioenvironmental trends and local (economic) dynamics. The intrinsic system's evolution observed at both regional and national level in Italy may be generalized to a broader European context. Our work finally documents the appropriateness of a multidimensional definition of desertification risk grounded on the joint analysis of ecological, demographic, economic, and administrative indicators. A comprehensive knowledge of socioeconomic patterns and processes of change contributes to more precise scenario modeling and design of integrated strategies mitigating desertification risk.     

A COVINDEX based on a GAM beta regression model with an application to the COVID-19 pandemic in Italy

Statistical Methods & Applications - Detecting changes in COVID-19 disease transmission over time is a key indicator of epidemic growth. Near real-time monitoring of the pandemic growth is...     

Re-randomization tests as sensitivity analyses to confirm immunological noninferiority of an investigational vaccine: Case study

Here we present as case study how re-randomization tests were performed in two randomized, controlled clinical trials as sensitivity analyses, as recommended by the United States Food and Drug Administration in the context of adaptive randomization. This was done to confirm primary conclusions on immunological noninferiority of an investigational new fully liquid presentation of a quadrivalent cross-reacting material conjugate meningococcal vaccine (MenACWY-CRM), over its licensed lyophilized/liquid presentation. In two phase 2b studies (Study #1: NCT03652610; Study #2: NCT03433482), noninferiority of the fully liquid presentation of MenACWY-CRM to the licensed presentation was assessed and demonstrated for immune responses against meningococcal serogroup A (MenA), the only vaccine component modified from lyophilized to liquid in the new presentation. The original vaccine assignment algorithm, with a minimization procedure accounting for center or center within age strata, was used to re-randomize participants belonging to the fully liquid and licensed vaccine groups while keeping antibody responses, covariates and entry order as observed. Test statistics under re-randomization were generated according to the ANCOVA model used in the primary analysis. To confirm immunological noninferiority following re-randomization, the corresponding p-values had to be <0.025. For both studies and all primary objective evaluations, the re-randomization p-values were well below 0.025 (0.0004 for Study #1; 0.0001 for the two co-primary endpoints in Study #2). Re-randomization tests performed to comply with a regulatory request confirmed the primary conclusions of immunological noninferiority for the MenA of the fully liquid compared to the licensed vaccine presentation.     

Determinants of Foreign Workers’ Wages in Two Italian Regions with High Illegal Immigration

Since the end of the 1970s Italy has moved from being an out-migration country to being a foreign immigration country, but very few studies have addressed the factors determining the wages of immigrant workers, owing to the lack of available data. In this paper we analyse the determinants of the wages of immigrants in some areas of Latium and Campania, where the share of illegal immigration is relatively high, using the results of a set of sample surveys which collected information on several aspects of the immigration process in the years 1993–94. The purpose of the article is to shed some light on the factors underlying wage distribution among the immigrants using an estimation method that controls for sample selection problems. According to the empirical results, income differences seem to be relatively high among immigrants. Differences in labour market integration among sexes and area of origin clearly emerge from the results. Moreover, legal status plays an important role in the explanation of the wage gap between documented and undocumented immigrants, also because of the different occupational sector structure in the two groups.     

Siblings in lockdown: International evidence for birth order effects on child adjustment in the Covid19 pandemic

Supportive family relationships may mitigate the impact of the Covid19 pandemic on young children's adjustment, but existing work is limited by its focus on within-country variation and parental influences. Addressing these gaps, and drawing on reported buffering effects of older siblings on child mental health (Lawson and Mace, 2010), the current international study examined whether child adjustment problems were, on average, elevated by the pandemic and whether this buffering effect of older siblings would be maintained. In the first wave of the Covid19 pandemic (April to July 2020), 2516 parents of 3- to 8-year-old children living in Australia, China, Italy, Sweden, United Kingdom, and United States of America—six countries with contrasting governmental responses to the pandemic—completed an online survey about family experiences and relationships and child adjustment, as indexed by ratings on the Strengths and Difficulties Questionnaire (SDQ: R. Goodman, 1997). As expected, child SDQ total difficulty scores were elevated in all sites except Sweden (which notably did not enforce mass school closures). Compared to children without siblings, children with one or more older siblings showed fewer adjustment problems. Children from lone-parent households displayed more adjustment problems, as did those whose parents reported increased sibling conflict. Finally, child adjustment problems were negatively associated with family socio-economic status, but positively related to the indices of Covid-19 family disruption and government stringency. We discuss these findings in relation to existing work on asymmetric effects of older versus younger siblings, and siblings as sources of support.     

Measuring residential segregation in multi-ethnic and unequal European cities

Immigration flows and social inequalities reflect increased social and multi-ethnic segregation in contemporary urban Europe. For a better understanding of these processes, the present study investigates the main strengths of the multi-group residential indices, testing sensitivity and reliability under different metropolitan contexts in five European countries. These indices focus on different research dimensions and approach multi-group residential segregation conceptually and mathematically in a different way. A multivariate exploratory data analysis was adopted to classify the observed segregation patterns into a few homogeneous types and to delineate the multivariate relationship between the indices. The results of principal component analysis demonstrate that the indices assessing uniformity and disproportionality of the social groups analysed (H and D) contribute largely to the diversification in today's multi-ethnic communities, clarifying the importance of the dimension of evenness. Our results highlight how segregation is more evident in economically disadvantaged metropolitan regions with high levels of social vulnerability.