The surprising effectiveness of earliest operation due-date sequencing

In make-to order production, schedule reliability is very important but still not sufficiently accomplished in industrial practice by the vast majority of companies. It has been known for long that processing the orders at a workstation in the order of their operation due-dates can compensate for lateness in the arrival at the workstation within certain boundaries. The paper analyses the effectiveness of earliest operation due date (EODD) sequencing by comparing it to an optimistic theoretical boundary. The surprising result is that EODD can nearly fully exploit the theoretical potential. It should therefore be used in practice whenever schedule reliability is important, with only few exceptions. Its effectiveness though is increasing with the workstation’s WIP level and thus is in conflict with the objective to reduce WIP levels and throughput times. A simple forecasting model allows to assess the extent to which lateness can be compensated by EODD sequencing and which schedule compliance can be achieved.     

Consolidated findings from 6 years research on the age-differentiated design of human-computer interaction

The fast aging of many western and eastern societies and their increasing reliance on information technology create a compelling need to reconsider older users' interactions with computers. This paper summarizes the results of 6 years of research on the age-differentiated design of human-computer interaction. The well-known model of human information processing served as the theoretical framework. The model components 'sensory processing', 'perception', 'working memory', 'decision and response selection' and 'response execution' were analyzed exemplarily in task settings on project management. In seven empirical studies with a total number of 405 participants between 20 and 77 years the human-computer interaction was analyzed regarding effectiveness, efficiency and user satisfaction. For most but not all studies the results reveal that age-induced differences in human-computer interaction can best be compensated by an ergonomic 'design for all'. In some cases however an age-specific approach is favorable.     

Estimating German overqualification with stochastic earnings frontiers

We estimate individual potential income with stochastic earnings frontiers to measure overqualification as the ratio between actual income and potential income. To do this, we remove a drawback of the IAB employment sample, the censoring of the income data, by multiple imputation. The measurement of overqualification by the income ratio is also a valuable addition to the overeducation literature because the well-established objective or subjective overeducation measures focus on some ordinal matching aspects and ignore the metric income and efficiency aspects of overqualification.     

Gedanken zur Gestaltung einer professionellen Beratungsausbildung

Considerations on the design of a professional education of counselorsSome of the recently published articles about supervision-professionalizing are reflecting only sociological or psychological conceptions in order to describe and analyze professionality. In this article the authors discuss some of the mostly neglected points of view out of pedagogic and microsociologic professionalization-research (professional self, researching attitude). The existing requests of competence for supervisors are examined in order to test their teaching ability. Furthermore the content designs and didactic strategies for future counselor’s education are considered.     

The Uniqueness of the Child–Father Attachment Relationship: Fathers' Sensitive and Challenging Play as a Pivotal Variable in a 16-year Longitudinal Study

This longitudinal study of forty‐four families explored fathers’ as compared to mothers’ specific contribution to their children's attachment representation at ages 6, 10, and 16 years. In toddlerhood, fathers’ and mothers’ play sensitivity was evaluated with a new assessment, the sensitive and challenging interactive play scale (SCIP). Fathers’ SCIP scores were predicted by fathers’ caregiving quality during the first year, were highly consistent across 4 years, and were closely linked to the fathers’ own internal working model of attachment. Qualities of attachment as assessed in the Strange Situation to both parents were antecedents for children's attachment security in the Separation Anxiety Test at age 6. Fathers’ play sensitivity and infant–mother quality of attachment predicted children's internal working model of attachment at age 10, but not vice versa. Dimensions of adolescents’ attachment representations were predicted by fathers’ play sensitivity only. The results confirmed our main assumption that fathers’ play sensitivity is a better predictor of the child's long‐term attachment representation than the early infant–father security of attachment. The ecological validity of measuring fathers’ sensitive and challenging interactive play behavior as compared to infant proximity seeking in times of distress is highlighted. Findings are discussed with respect to a wider view on attachment in that both parents shape their children's psychological security but each in his or her unique way.     

Firm size and board diversity

This study seeks to understand the relation between firm size and supervisory board composition. Specifically, we ask if and how firm size influences occupational and international background diversity in supervisory boards. Relying on resource dependence theory and theories of organizational behavior, we hypothesize that board diversity with respect to directors’ occupational background will increase with firm size, while the relation between firm size and board diversity with respect to directors’ international background will be concave. Using archival data for supervisory board members of 151 German firms listed in the German stock exchange indices DAX, MDAX, SDAX and TecDAX for the business year 2005, we find empirical support for our hypotheses: Both, occupational and international background diversity increase with increasing firm size, but international background diversity does so at decreasing rates.