Sequential Monte Carlo for rare event estimation

This paper discusses a novel strategy for simulating rare events and an associated Monte Carlo estimation of tail probabilities. Our method uses a system of interacting particles and exploits a Feynman-Kac representation of that system to analyze their fluctuations. Our precise analysis of the variance of a standard multilevel splitting algorithm reveals an opportunity for improvement. This leads to a novel method that relies on adaptive levels and produces, in the limit of an idealized version of the algorithm, estimates with optimal variance. The motivation for this theoretical work comes from problems occurring in watermarking and fingerprinting of digital contents, which represents a new field of applications of rare event simulation techniques. Some numerical results show performance close to the idealized version of our technique for these practical applications.     

Corporate social responsibility and corporate governance in Italian SMEs: the experience of some “spirited businesses”

The study proposes to individuate the relationship between social engagement, social statements and governance of SMEs. Does an adhesion to the philosophy and to the practices of CSR, which are reflected in a firm’s mission and accountability, positively influences its governance? If so, is this influence more or less significant for SMEs with respect to large-sized firms? This paper winds itself around these questions and describes the principle findings that have emerged from a qualitative investigation focused on a selected group of “cohesive” Italian SMEs, in which their management complies with both economic and social issues. The empirical study finds that the diffusion of CSR is tied above all to the entrepreneur’s values and orientation and to the company embeddedness to the local socio-economic environment. The concluding reflections trace the features of a territorial model of socially responsible orientation centered on the best practices of SMEs who are excellent examples of “spirited businesses” and are part of a network (which includes institutions, trade associations, non-profit organizations, etc.) that contributes to the diffusion of an orientation towards CSR and to sustainability across the territory.     

The role of grandparenting in early childcare and child outcomes

This paper examines the short and medium term impact of early childcare provision by grandparents and formal care settings on child cognitive outcomes, using data from the Millennium Cohort Study (UK). Compared with children placed in formal childcare, children cared for by their grandparents are better at naming objects, but perform worse on tests of basic concept development and non-verbal reasoning. These results mask strong heterogeneities. On the one hand, the positive association between grandparental care and child outcomes is stronger for children from more advantaged households; on the other, the negative association is only significant for those from more disadvantaged households. The results of OLS estimations used for our analysis are confirmed using panel methods and an instrumental variable approach.     

Post-Divorce Transfers and the Welfare of Mothers and Children in the United States

ABSTRACT In this paper we analyze the relationship between post-divorce private transfers (child support and alimony), mothers' economic independence and children's welfare using US data. Our empirical results show that mothers who receive child support and alimony from absent fathers are more likely to work and to spend a higher proportion of the income on child-related goods. We argue that the pattern of empirical results is consistent with there being significant externalities between parents even after divorce.     

Value-added distribution to stakeholder of Spanish listed companies: a corporate governance perspective

Journal of Management and Governance - Following a stakeholder corporate governance perspective, we examine whether the characteristics of boards of directors (board size, separation of Chairman...     

Usability and Feasibility Study of a Remote Cognitive Behavioral Therapy System with Long-Term Unemployed Women

We present the results of the use of a cognitive behavioral therapeutic intervention tool to improve the mental, physical, and social health of a group of long-term unemployed women in Spain. Method: We sent automated text messages (SMS) to the mobile phones of long-term unemployed women selected at random from public social services. During a 28-day intervention period, women received four daily automated text messages on her mobile phone on a predetermined hourly schedule. We measured depression symptoms at the start and end of the intervention and we analyzed qualitative data to determine the acceptability of a remote SMS program. Results: Depression symptoms using the Personal Health Questionnaire-9 (PHQ-9), went from an average of 13.8 at baseline to 4.9 at the end of 28 days (p?=?0.89). One hundred percent of the women reported that they liked receiving the text messages and most found them helpful.     

Daring to care: the role of culturally relevant care in mentoring Black and Latino male high school students

This study seeks to challenge the uni-dimensional way care in school is written about by highlighting an often overlooked aspect of care – the kind that students do for each other. Data is drawn from focus groups conducted with the youth participants and founder of Umoja Network for Young Men (UMOJA), an all-male, school-based mentoring program for over-aged and under-credited (OA/UC) high school students. The authors draw on theories of culturally relevant pedagogy, care, and critical pedagogy to present the findings and propose a form of culturally relevant care (CRC) that entails warm demanding and building mutual trust. This study highlights the humanizing experiences of the Black and Latino male transfer students and their mentor. This focus on the experiences of young Black and Latino male participants seeks to shift the discourse from one focused on deficits to one that recognizes their agency and capacities for social and academic success.     

Risk of Error and the Kappa Coefficient of a Binary Diagnostic Test in the Presence of Partial Verification

The accuracy of a binary diagnostic test is usually measured in terms of its sensitivity and its specificity, or through positive and negative predictive values. Another way to describe the validity of a binary diagnostic test is the risk of error and the kappa coefficient of the risk of error. The risk of error is the average loss that is caused when incorrectly classifying a non-diseased or a diseased patient, and the kappa coefficient of the risk of error is a measure of the agreement between the diagnostic test and the gold standard. In the presence of partial verification of the disease, the disease status of some patients is unknown, and therefore the evaluation of a diagnostic test cannot be carried out through the traditional method. In this paper, we have deduced the maximum likelihood estimators and variances of the risk of error and of the kappa coefficient of the risk of error in the presence of partial verification of the disease. Simulation experiments have been carried out to study the effect of the verification probabilities on the coverage of the confidence interval of the kappa coefficient.