(Un)Gleichheit durch soziale Schlie?ung

The concept of social closure is frequently used in recent debates about wage inequality. The following article shows that social closure generates not only inequality but equality, as well. Economic, segmentational and closure theoretical arguments shed light on the different relations of an employee to his employer in different labour market structures. Properties of the employee like vocational training, seniority or gender lose their impact on wages the more closed a labour market is. These hypotheses are tested with the 2006 BIBB/BAuA-Employment-Survey. Results support a deep effect of social closure in the German labour market.     

Sensitivity Analysis Using Risk Measures

In a quantitative model with uncertain inputs, the uncertainty of the output can be summarized by a risk measure. We propose a sensitivity analysis method based on derivatives of the output risk measure, in the direction of model inputs. This produces a global sensitivity measure, explicitly linking sensitivity and uncertainty analyses. We focus on the case of distortion risk measures, defined as weighted averages of output percentiles, and prove a representation of the sensitivity measure that can be evaluated on a Monte Carlo sample, as a weighted average of gradients over the input space. When the analytical model is unknown or hard to work with, nonparametric techniques are used for gradient estimation. This process is demonstrated through the example of a nonlinear insurance loss model. Furthermore, the proposed framework is extended in order to measure sensitivity to constant model parameters, uncertain statistical parameters, and random factors driving dependence between model inputs.     

Choosing summary statistics by least angle regression for approximate Bayesian computation

Bayesian statistical inference relies on the posterior distribution. Depending on the model, the posterior can be more or less difficult to derive. In recent years, there has been a lot of interest in complex settings where the likelihood is analytically intractable. In such situations, approximate Bayesian computation (ABC) provides an attractive way of carrying out Bayesian inference. For obtaining reliable posterior estimates however, it is important to keep the approximation errors small in ABC. The choice of an appropriate set of summary statistics plays a crucial role in this effort. Here, we report the development of a new algorithm that is based on least angle regression for choosing summary statistics. In two population genetic examples, the performance of the new algorithm is better than a previously proposed approach that uses partial least squares.     

CCR or BCC: what if we are in the wrong model?

The CCR model by Charnes et al. (Eur J Oper Res 2:429–444, 1978) together with the BCC model by Banker et al. (Manag Sci 30:1078–1091, 1984) are the most popular approaches of measuring efficiency among a group of decision making units, DMUs, in data envelopment analysis, DEA. The right choice of a DEA model—CCR or BCC—often, if not always, is a difficult decision. To evaluate a DMU’s efficiency for both models might be helpful, but it does not always capture the essential issues at stake. In this paper we propose a comparative analysis of both concepts: How does activity scaling under constant BCC-efficiency influence CCR-efficiency. And inversely, how does BCC-efficiency behave when activity scaling under constant CCR-efficiency is applied. Such findings of mutual effects improve a DMU’s ability to reassess upsizing and downsizing of activities. Moreover, it allows for exact calculations of the resulting economic effects, and these effects give new insights beyond classical DEA. Finally, scale efficiency turns out to be the ideal concept to control these activity changes, rather than just CCR- or BCC-efficiency. We use a little numerical example to emphasize advantages of the new concept and sketch the new findings for a theater scenery.     

Measuring servitization progress and outcome: the case of ‘advanced services’

The purpose of this paper is to establish a framework for assessing the progress and outcome of a manufacturer’s transformation towards becoming a provider of ‘advanced services’ – a complex bundling of products and services, whereby manufacturers offer capabilities and outcomes instead of products alone. ‘Advanced services’ represent the most complex offering in the current servitization trend amongst manufacturers. However, current performance measures lack the breadth and focus to assess progress or outcomes, and so support research and practice of organisational transformation efforts required. To address this gap the paper investigates how a manufacturer’s efforts to become an ‘advanced services’ provider can be comprehensively measured, and develops a framework for assessing the transformation journey towards becoming an ‘advanced services’ provider. The research method is based on (1) a systematic literature review process to create a comprehensive set of service-related performance measures that are available to assess a manufacturer’s servitization efforts, followed by (2) an engagement with an expert panel to synthesise the identified measures and create a set of ‘advanced services’ performance measures. The proposed framework is presented as a scorecard that can be used in practice to assess the progress and outcome of a manufacturer’s transformation towards becoming a provider of ‘advanced services’.     

Discourses of service user involvement in meeting places in Norwegian community mental health care: a discourse analysis of staff accounts

In previous research, meeting places have been favourably addressed by service users, but they have also been contested as exclusionary. In this participatory explorative study, we sought to perform a contextual analysis of meeting places in Norway based on a discourse analysis of three focus group discussions with 15 staff members. We asked the following question: how do meeting-place employees discuss their concrete and abstract encounters with service users and their experiences? We focused on service user involvement, which was largely analysed as neoliberal consultation and responsibilisation. Service users were positioned as resisting responsibility trickling down and defending staffed meeting places. Social democratic discourse was identified in the gaps of neoliberal discourse, which is noteworthy given that Norway is a social democracy. This relates to global concerns about displacements of democracy. We suggest that meeting places appear to hold the potential for staff and service users to collaborate more democratically.     

Der regulatorische Fokus als Führungsinstrument für eine bedürfnisorientierte und effektive Mitarbeiterkommunikation

Interaction with employees is essential for organizational leaders. If executives do not communicate well, important processes like giving feedback, setting goals or guiding change processes can nevertheless lead to resistance from subordinates when communication is received as more threatening than challenging. Conveying messages in ways that provoke challenge instead of threat appraisals can be achieved via employee-oriented communication, but this may require taking peoples’ differing motivational orientations into account. This is because motivational orientations partially determine what kind of information is motivating to us, which goals and strategies we prefer, and how we deal with changes. In this regard, Regulatory Focus Theory (Higgins 1997) compares the gain- and success-sensitive promoter with the loss- and failure-sensitive preventer. This article applies this theory to the organizational psychological context and outlines practical implications for managers. The goal of the piece is to provide managers a leadership tool that acknowledges the diversity of peoples’ motivational styles and by that revealing a need-oriented and more efficient way in communication with subordinates.     

Optimization problems with color-induced budget constraints

In 1984, Gabow and Tarjan provided a very elegant and fast algorithm for the following problem: given a matroid defined on a red and blue colored ground set, determine a basis of minimum cost among those with k red elements, or decide that no such basis exists. In this paper, we investigate extensions of this problem from ordinary matroids to the more general notion of poset matroids which take precedence constraints on the ground set into account. We show that the problem on general poset matroids becomes -hard, already if the underlying partially ordered set (poset) consists of binary trees of height two. On the positive side, we present two algorithms: a pseudopolynomial one for integer polymatroids, i.e., the case where the poset consists of disjoint chains, and a polynomial algorithm for the problem to determine a minimum cost ideal of size l with k red elements, i.e., the uniform rank-l poset matroid, on series-parallel posets.     

Promoting work ability and well-being in hospital nursing: the interplay of age, job control, and successful ageing strategies

Previous research shows that work ability of nurses decreases with age. In our study we therefore addressed the following questions: Do successful ageing strategies at work in terms of selection, optimization, and compensation (SOC) support the work ability of nurses? Does SOC mediate the relationship between job control (i.e., decision opportunities at work) and work ability? Does the mediation differ between age-groups? 438 nurses (Age Range 21-63 years) completed a questionnaire in the course of an employee survey. Results show that SOC is positively related with work ability. The positive effect of job control on work ability is significantly mediated by SOC. There are stronger mediating effects for elder nurses than for younger nurses. Results indicate that the interplay of job control and SOC at work helps to maintain the work ability of nurses in nursing care.     

Manual flying skills under the influence of performance shaping factors

This paper describes an experimental study investigating pilots' manual flying skills. In today's line oriented flight training, basic flying skills are neglected frequently. So, the study examines the manual flying skills of commercial airline pilots under the influence of several performance shaping factors like training, practice or fatigue in a landing scenario. The landing phase shows a disproportionate high percentage of aircraft accidents and it is typically flown by hand. The study is to be undertaken with randomly selected pilots in a full motion flight simulator to ensure a high validity of the results.