Statistical and Combinatorial Aspects of Comparative Genomics*

Abstract. This document presents a survey of the statistical and combinatorial aspects of four areas of comparative genomics: gene order based measures of evolutionary distances between species, construction of phylogenetic trees, detection of horizontal transfer of genes, and detection of ancient whole genome duplications.     

Participation for children exposed to domestic violence? Social workers' approaches and children's strategies

This article explores social workers' approaches to children exposed to domestic violence and children's strategies in encounters with these professionals in the context of family law proceedings. Investigator approaches as well as child strategies are reconstructed from children's narratives. Furthermore, possible links between the social worker's approach described by a particular child, and the child's own strategies are outlined. Participation can offer children validation of their experiences and support their recovery after exposure to violence. However, it is suggested that it seems to be a challenging task for social workers to both validate children's experiences of violence and simultaneously offer them participation in the investigation process.     

Decision model for product rollover in manufacturing operations

The purpose of this study is to investigate critical decisions when planning for product rollover at a manufacturing company, and how to organise these decisions. A literature review and a case study are used to develop a decision model. The findings indicate that product rollover can be organised in a five-phase decision model. The research quality is strengthened by a structured literature review, but it can be argued that more empirical research is needed for validation. For researchers, this paper contributes with the identification of critical decisions and a model for product rollover. For practitioners, the study highlights the need to acknowledge the importance of product rollover and its role as a competitive weapon. In earlier studies, product rollover has mainly been investigated from a market perspective, so that this study contributes by investigating the issue from a manufacturing perspective.     

A Proportional Hazards Regression Model for the Subdistribution with Covariates‐adjusted Censoring Weight for Competing Risks Data

With competing risks data, one often needs to assess the treatment and covariate effects on the cumulative incidence function. Fine and Gray proposed a proportional hazards regression model for the subdistribution of a competing risk with the assumption that the censoring distribution and the covariates are independent. Covariate‐dependent censoring sometimes occurs in medical studies. In this paper, we study the proportional hazards regression model for the subdistribution of a competing risk with proper adjustments for covariate‐dependent censoring. We consider a covariate‐adjusted weight function by fitting the Cox model for the censoring distribution and using the predictive probability for each individual. Our simulation study shows that the covariate‐adjusted weight estimator is basically unbiased when the censoring time depends on the covariates, and the covariate‐adjusted weight approach works well for the variance estimator as well. We illustrate our methods with bone marrow transplant data from the Center for International Blood and Marrow Transplant Research. Here, cancer relapse and death in complete remission are two competing risks.     

Overcoming the Glass Barriers: Reflection and Action in the ‘Women to the Top’ Programme

Numerous equality programmes have been launched with the aim of promoting a more gender equal work life, yet little substantial action has been reported. This article presents a study of the Women to the Top programme in Sweden, supported by the European Union (EU) and aimed at promoting more women into top management positions. The research suggests that large‐scale projects assembling such heterogeneous actors as industry representatives, politicians and scholars tend to generate further reflection and discussion rather than promoting adequate and highly needed action. Drawing upon Brunsson's distinction between action rationality and decision rationality, the relatively modest effects of large‐scale equality programmes are examined, not in terms of a lack of commitment or competence on the part of the participants but as a matter of the disjunction between reflection and action. Reconciling reflection and action, that is, emphasizing not only reflection on gender inequality but also privileging various forms of practical action (such as new policies, the appointment of female managers, restructuring gendered wage inequalities or new recruitment procedures), is therefore a top priority for policymakers desiring more substantial changes in the gendered outline of industry.     

The satisfaction of Finnish adoptive parents with statutory pre-adoption counselling in inter-country adoptions

We examined how satisfied Finnish adoptive parents were with statutory pre-adoption counselling in inter-country adoptions. The data were collected through the Finnish Adoption Study using a retrospective survey measuring satisfaction with received pre-adoption counselling. All adoptive parents with a child under the age of 18, adopted from abroad between the years 1990 and 2007, were included. The sample of the study comprised parents of 1451 children and a total response rate of 55.7% was achieved. The data consisted of self-scored reports of satisfaction as well as open answer questions. Parent satisfaction and associated variables were analysed using chi-square and multiple logistic regression. Of the respondents, 81.7% reported satisfaction with the pre-adoption counselling they had received. The level of satisfaction was stable over time and did not differ according to service provider, whereas family type and sending country were associated with satisfaction. However the explanations for satisfaction were different for those services provided in units specialized in adoption and for those provided by municipal child protection services. The components found to explain satisfaction and dissatisfaction were experience, adoption knowledge, and attitude of the social worker, service accessibility and availability issues, as well as the content of the pre-adoption counselling offered.     

Unemployment and mental health: evidence from research in the Nordic countries

In this article we examine research on effects of unemployment on mental health in Denmark, Finland, Norway and Sweden. We describe studies that use cross-sectional, longitudinal and time-series data, and we discuss studies that investigated the duration-dependence issue in exit rates out of unemployment. Not surprisingly, cross-sectional studies reveal that unemployed persons have worse mental health than do others. Most longitudinal studies suggest that unemployment is associated with deteriorating mental health, even though it is somewhat unclear how long such an effect persists. Most duration-dependence studies were done using Swedish data. It turns out that unemployment benefits and labour-market policies affect the pattern of exit rates out of unemployment.     

Endocrine markers during a job intervention

An intervention consisting of a thorough examination of the psychological worksite problems and a follow-up with feedback and recommendations was made in four different office worksites. One of the sites («active» group) was more organizational change-oriented than the others («passive» group). The course was followed before, three times during the 3 months of the intervention, and 4 months after the end of it, by means of three endocrine plasma markers: cortisol, prolactin and testosterone. In both study groups the prolactin levels increased in women during the starting phase of the intervention, whereas in men prolactin levels remained stable with a tendency (p=0.06) towards lowered prolactin levels during the end phase of the intervention in the active group. Cortisol levels increased markedly in the passive group and tended to decrease in the active group during the intervention (two-way interaction p=0.003), particularly in men. These findings may be indicative of feelings of uneasiness. Testosterone increased in the active group only, particularly at the beginning of the intervention and particularly in women, and also increased in a non-intervention control group. Testosterone levels are associated with anabolic activity. An increase may be indicative of a «placebo effect» of the intervention. Testosterone changes were still clearly observable after 4 months.     

Modeling service-time distributions for queueing network simulation

Shapes of service-time distributions in queueing network models have a great impact on the distribution of system response-times. It is essential for the analysis of response-time distribution that the modeled service-time distributions have the correct shape. Tradionally modeling of service-time distributions is based on a parametric approach by assuming a specific distribution and estimating its parameters. We introduce an alternative approach based on the principles of exploratory data analysis and nonparametric data modeling. The proposed method applies nonlinear data transformation and resistant curve fitting. The method can be used in cases, where the available data is a complete sample, a histogram, or the mean and a set of 5-10 quantiles. The reported results indicate that the proposed method is able to approximate the distribution of measured service times so that accurate estimates for quantiles of the response-time distribution are obtained     

Firm‐level Consequences of Large Minimum‐wage Increases in the Czech and Slovak Republics

Abstract. After an initial decline in the level of real minimum‐wage rates, there were series of unusually large increases in their levels — 70 and 50 per cent — during the years 1999–2002 in the Czech and Slovak Republics, respectively. Using information from matched employee–employer data sets, we look at the impact of minimum‐wage hikes on both wages and employment. Our results suggest that there are some, but not substantial, job losses in reaction to minimum‐wage hikes and that the impact on firm wages is rather large, implying that further increases of similar magnitude might very well have negative consequences for employment.