Disentangling the sources of variation in the survival of the European dipper

The population growth rate of the European dipper has been shown to decrease with winter temperature and population size. We examine here the demographic mechanism for this effect by analysing how these factors affect the survival rate. Using more than 20 years of capture-mark-recapture data (1974-1997) based on more than 4000 marked individuals, we perform analyses using open capture-mark-recapture models. This allowed us to estimate the annual apparent survival rates (probability of surviving and staying on the study site from one year to the next one) and the recapture probabilities. We partitioned the variance of the apparent survival rates into sampling variance and process variance using random effects models, and investigated which variables best accounted for temporal process variation. Adult males and females had similar apparent survival rates, with an average of 0.52 and a coefficient of variation of 40%. Chick apparent survival was lower, averaging 0.06 with a coefficient of variation of 42%. Eighty percent of the variance in apparent survival rates was explained by winter temperature and population size for adults and 48% by winter temperature for chicks. The process variance outweighed the sampling variance both for chick and adult survival rates, which explained that shrunk estimates obtained under random effects models were close to MLE estimates. A large proportion of the annual variation in the apparent survival rate of chicks appears to be explained by inter-year differences in dispersal rates.     

The effectiveness of couple therapy in Germany: a replication study

The utility of couple therapy has been investigated in a number of controlled clinical efficacy investigations, demonstrating the superiority of most forms of couple therapy relative to control groups. Despite its widespread use, the effectiveness of couple therapy in field settings is largely unknown. In 1997, Hahlweg and Klann published an effectiveness study of couple therapy as practiced in German and Austrian marital counseling agencies. The purpose of the current investigation was to replicate their earlier findings in a similar setting with identical measures. The findings demonstrate that the results are remarkably similar across the two studies and that couple therapy in these applied settings helps to alleviate relationship distress as well as individuals' depression.     

The experience of giving birth with epidural analgesia

Problem and backgroundThere is a lack of literature about what constitutes good midwifery care for women who have epidural analgesia during labour. It is known that an increasing number of women receive epidural analgesia for labour pain. We also know that while women rate the painkilling effect of the epidural analgesia as high, in general, their satisfaction with labour is unchanged or even lower when epidural analgesia is used.QuestionHow do women experience being in labour with epidural analgesia, and what kind of midwifery care do they, consequently, need?MethodsA field study and semi-structured interviews were conducted on a phenomenological basis. Nine nulliparous women were observed from initiation of epidural analgesia until birth of their baby. They were interviewed the day after the birth and again 2 months later. The involved midwives were interviewed 2–3 h after the birth.FindingsInitiation of epidural analgesia can have considerable implications for women's experience of labour. Two different types of emotional reactions towards epidural analgesia are distinguished, one of which is particularly marked by a subtle sense of worry and ambivalence.Another important finding refers to the labouring woman's relationship with the midwife, which represents an essential influencing factor on the woman’ experience of labour. Within this relationship, some rather unnoticed matters of communication and recognition appear to be of decisive significance.ConclusionAfter initiation of epidural analgesia the requirements of midwifery care seem to go beyond how women verbalise and define their own needs. The midwife should be attentive to the labouring woman's type of emotional reaction to epidural analgesia and her possible intricate worries.     

Investigation of age–treatment interaction in the SPACE trial using different statistical approaches

Selection of treatments to fit the specific needs for a certain patient is one major challenge in modern medicine. Personalized treatments rely on established patient–treatment interactions. In recent years, various statistical methods for the identification and estimation of interactions between relevant covariates and treatment were proposed. In this article, different available methods for detection and estimation of a covariate–treatment interaction for a time-to-event outcome, namely the standard Cox regression model assuming a linear interaction, the fractional polynomials approach for interaction, the modified outcome approach, the local partial-likelihood approach, and STEPP (Subpopulation Treatment Effect Pattern Plots) were applied to data from the SPACE trial, a randomized clinical trial comparing stent-protected angioplasty (CAS) to carotid endarterectomy (CEA) in patients with symptomatic stenosis, with the aim to analyse the interaction between age and treatment. Time from primary intervention to the first relevant event (any stroke or death) was considered as outcome parameter. The analyses suggest a qualitative interaction between patient age and treatment indicating a lower risk after treatment with CAS compared to CEA for younger patients, while for elderly patients a lower risk after CEA was observed. Differences in the statistical methods regarding the observed results, applicability, and interpretation are discussed.     

Antecedents of knowledge sharing - Examining the influence of learning and performance orientation

Knowledge sharing is an important process in creating competitive advantage. Previous literature mainly identifies environmental and organizational factors that influence the effective transfer of knowledge. However, the focus shifts to the analysis of personal determinants as antecedents for the individual’s engagement in knowledge sharing activities, like personality traits. In this paper, we introduce employees’ goal orientations (i.e. learning orientation or performance orientation) to the individual antecedents of knowledge sharing behavior. It is argued that learning orientation positively influences knowledge sharing, whereas performance orientation is a negative influence factor. As goal orientations are determined by personality traits, we can also confirm existing hypotheses regarding this relationship. The theoretical model developed in this paper is empirically tested on a sample of 124 engineers of an internationally operating engineering company, and significant relationships among the constructs were found.     

The Influence of Proactive Personality and Coping on Commitment to STEM Majors

Despite increasing demand for workers in fields that are grounded in science, technology, engineering, and math (STEM), retention rates are low among relevant college majors. Using Web‐based survey data from 290 STEM majors, the authors investigated links among personality, coping strategies, and STEM major commitment. Proactive personality was positively related to STEM major commitment and to the active planning coping strategy and negatively related to behavioral disengagement. Active planning was positively related to commitment to STEM majors and behavioral disengagement was negatively related to the outcome. Coping strategies fully mediated the relationship between proactive personality and commitment to STEM majors.     

Wives and widows in medieval Flanders

Widowhood has long been regarded as the most emancipated condition that women might enjoy, affording them a freedom, agency and access to the public sphere denied their single or married counterparts. A corollary of this assumption is that most women documented as active participants in public life should be identified as widows. Based on a large corpus of references to female activity in bailiffs’ accounts and in town records and ordinances, however, this article argues that in pre-Burgundian Flanders widowhood in no way constituted a privileged status, either morally, socially, legally or economically. Flemish women were educated in order that they might achieve gainful employment; they married late and maintained control of property in marriage. Married women functioned as legal persons; they participated publicly, independently and routinely in Flemish urban life to such a degree that their subsequent activities as widows can only be understood as being in fundamental continuity with their prior behaviour as wives. This, in conjunction with the ambiguity and instability of terms for ‘women whose spouses are deceased’, destabilized the very concept of ‘widow’ itself.     

Critical objective function values in linear sum assignment problems

The linear sum assignment problem has been well studied in combinatorial optimization. Because of the integrality property, it is a linear programming problem with a variety of efficient algorithms to solve it. In the given research, we present a reformulation of the linear sum assignment problem and a Lagrangian relaxation algorithm for its reformulation. An important characteristic of the new Lagrangian relaxation method is that the optimal Lagrangian multiplier yields a critical bottleneck value. Lagrangian relaxation has only one Lagrangian multiplier, which can only take on a limited number of values, making the search for the optimal multiplier easy. The interpretation of the optimal Lagrangian parameter is that its value is equal to the price that must be paid for all objects in the problem to be assigned.