Rotation test with pairwise distance measures of sample vectors in a GLM

One way to cope with high-dimensional data even in small samples is the use of pairwise distance measures—such as the Euclidean distance—between the sample vectors. This is usually done with permutation tests. Here we propose the application of exact parametric rotation tests which are no longer restricted by the finite number of possible permutations of a sample. The method is presented in the framework of the general linear model.     

Child Care,Maternal Employment,and Children’s School Outcomes. An Analysis of Italian Data

In this paper we analyse the impact of mothers’ employment status and formal child care attendance during early childhood on children’s school grades later in life, controlling for socio-demographic factors. We use the year 2008 of the Italian ISFOL-PLUS dataset. The dataset provides information on each respondent’s demographic characteristics, as well as a set of retrospective information on the individual’s school grades at the end of junior high school, high school, and university, along with (in the 2008 wave only) information about the respondent’s formal child care attendance and mother’s employment status when he or she was under age of three. We estimate the effects of maternal employment and child care attendance on the probability that the respondent would have high grades at the end of high school. Since maternal employment and child care attendance are likely to be endogenously determined, we use an instrumental variable approach. Our empirical results show that while having a mother who was working (during early childhood) had no significant effect on an individual’s high school grades, child care attendance had a positive and significant effect. These results have potential policy implications. As maternal employment does not seem to negatively affect the development process of children, while child care attendance appears to have a positive impact on academic achievement, policy makers should consider expanding the availability of child care and promoting women’s participation in the labour market.     

Census data issues for epidemiology and health risk assessment: experiences from the Small Area Health Statistics Unit

Summary.  Census data are vital components of epidemiological studies, but the issues that are involved in using these data in such studies are often not fully appreciated. The paper describes some of the problems and uncertainties that arise, and some of the approaches that can be used to address them, based on experience in the Small Area Health Statistics Unit at Imperial College London. Issues considered include the geography of census data (zone design systems, recasting and the role of postcodes), temporal aspects of census data (especially in relation to migration and population change) and information content (especially in relation to characterization of socio-economic status). In the light of these issues, opportunities to improve the resolution and utility of census data for epidemiological studies are discussed.     

Zum Einfluss der Mandatsdauer des Abschlusspr��fers auf die Pr��fungsqualit?t

This study provides evidence on the relation between auditor tenure and audit quality. It is motivated by calls for mandatory auditor rotation, which are based on concerns that longer auditor tenure reduces auditor independence and thus audit quality. Earnings management is used as proxy for audit quality and is measured by absolute and signed performance-adjusted-Jones-model discretionary accruals. Multivariate analyses, controlling for additional firm and auditor characteristics indicate lower earnings management with longer auditor tenure. This result suggests that, in the current environment, mandatory limitations on the length of auditor-client-relationship would result in lower audit quality.     

Return to work after childbirth: does parental leave matter in Europe?

This paper investigates the role of the extended parental leave in the return to work for mothers of newborn children. Exploiting the variability in policies offered by the European countries, the paper studies the influence of statutory leave characteristics—length of the job-protection and payments during the leave-period—on the hazard of returning to work at different ages of the child. Results suggest that longer periods of job-protection increase the hazard of returning to work; on the other hand, providing paid leaves increases the probability of remaining at home during the first year of life of the child.     

Law Enforcement and Firm Financing: Theory and Evidence

This paper investigates the economic effects on firms' policies of differences in law enforcement. We find that in judicial districts where trials are longer, bank financing is more costly and firms are smaller. However, we do not find any significant relation between law enforcement and firms' leverage ratio. We rationalize our results within a two‐ region dynamic general equilibrium model with asymmetric information and collateralized credit contracts. We find that a stronger enforcement of creditors' rights not only improves credit conditions (partial equilibrium effect), but also fosters individual capital accumulation (general equilibrium effect). In line with this theoretical prediction, we find a positive relation between individual savings and quality of legal enforcement. (JEL: E20, K40, G32)     

The risk of partner aggression research: impact of laboratory couples conflict protocols on participants

The impact of male-to-female intimate partner violence (IPV) research on participants is unknown. A measure of impact was given to participants in an IPV study to assess systematically the impact of completing questionnaires, engaging in conflict conversations, and being interviewed individually about anger escalation and de-escalation during the conversations. Participants completed a six-question, Likert-scaled impact measure. Both male and female participants rated the impact of the study as helpful to them personally and to their relationships. Female participants rated different segments of the study as more helpful to themselves and their relationships, while male participants did not find any segment of the study to have a different impact than other segments.     

Overconfidence in absolute and relative performance: The regression hypothesis and Bayesian updating

Studies have found that people are overconfident in estimation involving difficult tasks but underconfident in easy tasks. Conversely, they are overconfident in placing themselves in easy tasks but underconfident in hard tasks. These findings can be explained by a regression hypothesis that implies random errors in estimation as well as by rational Bayesian updating (that implies no random error). We test these hypotheses in five experiments. We find overconfidence in estimation involving hard tasks but underconfidence in easy tasks. However, for placement (involving both easy and hard tasks) we find no overconfidence, regression effects due to low and high anchor points, and extreme underconfidence when people choose between multiple alternatives. On the other hand, when given precise information about absolute performance, people’s re-assessments of relative performance are consistent with the Bayesian model. Since placement judgments are important in many competitive settings, our results emphasize the need for more research to identify their determinants.     

Lean-healthcare approach to reduce costs in a sterilization plant based on surgical tray rationalization

Abstract

Sterilization plants process all reusable materials used in hospitals during different stages of healthcare provision. Most items sterilized come from the surgical theater in the form of individual instruments, linen and surgical trays. Reducing the number of instruments in trays impacts on the performance of the sterilization process. Here, we propose a three-phase method, based on lean healthcare principles, cluster analysis and kaizen groups of experts to rationalize surgical trays, reducing sterilization processing costs. We innovate by proposing a strategy to approach tray rationalization prioritizing surgical specialties that are both complex and frequent, and by using group technology to cluster surgical trays expediting expert analyses carried out by kaizen groups. Our propositions were tested in a high complexity, tertiary care hospital, covering 12 surgical specialties, reducing the number of instruments by average 9.75%, and the time-to-assemble trays by average 9.68%, obtaining annual savings of US$285.756,00 in sterilization processing costs.