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.     

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.     

Lessons from the Grey Area: A Closer Inspection of At-risk Gamblers

The study takes a closer look at at-risk gamblers, with the objective to see how they differ from no-risk gamblers. The data comes from a national gambling survey in 2002, and the age group is 15–74 years. The sample consists of 4188 current gamblers with no current gambling problems or pathology. The analysis includes cross-tabulations and a logistic regression. The results show that at-risk gamblers differed substantially from no-risk gamblers in terms of demographic characteristics, gambling behaviour and the presence of other assumed risk factors. Demographic segments with a higher risk of falling into the at-risk group are men, young people, divorced or single people, and non-western immigrants. Furthermore, gambling problems in the family, beginners luck and misconceptions about winning chances significantly increased the odds for at-risk gambling. The study concludes that at-risk gamblers deserve more attention from research, that their similarity with problem gamblers increases the likelihood that many of them will eventually develop a gambling problem, and that their tendency to be superstitious about winning chances might be exploited in preventive work.     

Estimates of subgroup treatment effects in overall nonsignificant trials: To what extent should we believe in them?

In drug development, it sometimes occurs that a new drug does not demonstrate effectiveness for the full study population but appears to be beneficial in a relevant subgroup. In case the subgroup of interest was not part of a confirmatory testing strategy, the inflation of the overall type I error is substantial and therefore such a subgroup analysis finding can only be seen as exploratory at best. To support such exploratory findings, an appropriate replication of the subgroup finding should be undertaken in a new trial. We should, however, be reasonably confident in the observed treatment effect size to be able to use this estimate in a replication trial in the subpopulation of interest. We were therefore interested in evaluating the bias of the estimate of the subgroup treatment effect, after selection based on significance for the subgroup in an overall “failed” trial. Different scenarios, involving continuous as well as dichotomous outcomes, were investigated via simulation studies. It is shown that the bias associated with subgroup findings in overall nonsignificant clinical trials is on average large and varies substantially across plausible scenarios. This renders the subgroup treatment estimate from the original trial of limited value to design the replication trial. An empirical Bayesian shrinkage method is suggested to minimize this overestimation. The proposed estimator appears to offer either a good or a conservative correction to the observed subgroup treatment effect hence provides a more reliable subgroup treatment effect estimate for adequate planning of future studies.     

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.     

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.     

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.     

Object Relations Family Therapy: Articulating the Inchoate

In recent years there has been a renewed interest in psychodynamic ideas within the family therapy literature. While some authors have explored the usefulness of psychodynamic concepts in the systemic context (Byng-Hall, 1995; Flaskas, 1993, 1996; Luepnitz, 1988, 1997), others have argued that psychodynamic models of family therapy should be given more credence in systemic work with families (Guttman, 1991). This paper describes Object Relations Family Therapy (ORFT), a psychoanalytic model of family therapy, in plain English in order to minimise the obscurity of some of the existing terminology and to emphasise the utility of more contemporary formulations. ORFT addresses the interface between psychoanalytic and systemic theories. It offers a way of conceptualising complex family dynamics at both the interpersonal and intrapsychic levels. It also integrates an understanding of nonverbal, unstated and often implicit processes in its formulation of problem development. The unique contribution of ORFT is elaborated using a clinical example.     

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.