Bargaining over waiting time in ultimatum game experiments

While preference-based explanations play an increasing role in economics and sociology, the accurate measurement of social preferences deserves more attention. Most laboratory experiments measure social preferences by studying the division of “a cake that nobody had to bake” (Güth and Kliemt, 2003). This article reports results of the first ultimatum game experiment with bargaining over waiting time. The experiment was created to avoid effects of windfall gains. In contrast to donated money, time is not endowed by the experimenter and implies a natural loss to subjects. This allows for a better measurement of the inherent conflict in the ultimatum game. We implemented three anonymity conditions; one baseline condition, one condition with anonymity among subjects and one double-blind condition in which the experimenter did not know the division of waiting time. While we expected to observe less other-regarding behavior in ultimatum game bargaining over time, our experimental results rather confirm previous ultimatum game experiments, in which people bargained over money. The modal offer was half of the waiting time and only one offer was rejected. Interestingly, anonymity did not change the results significantly. In conclusion, our experiment confirms other-regarding behavior in the ultimatum game.     

Sektion Soziologie und Ökologie

Ohne Zusammenfassung     

Gentrifikation in zwei Wohngebieten von KölnGentrification in two residential areas of Cologne

We examine the process of Gentrification in two residential areas of Cologne, Germany: Deutz and Mülheim. The theory underlying the study is a phase (or stage) model of Gentrification in which indicators and their values are attributed to each phase. The hypotheses derived from the model pertain to changes in the social structure, rents and the spatial distribution of social groups such as “pioneers”, “gentrifiers” and “others”. We further assume both areas to be in different phases of Gentrification.     

Personality factors predicting changes in shift work tolerance: A longitudinal study among nurses working rotating shifts

Abstract

The aim of the present study was to investigate the relationship between personality factors (hardiness, morningness, flexibility, and languidity) and longitudinal changes on different measures of shift work tolerance (fatigue, sleepiness, anxiety and depression) over one year among nurses working rotating shifts. A total of 642 female Norwegian nurses working in a rotating three-shift schedule participated in the study. The cohort was established by age-stratified selection among members of the Norwegian Nurses Association in 2008. Questionnaires were administered in 2008/2009 (T1) and in 2009/2010 (T2). The results showed that hardiness was negatively related to fatigue, anxiety and depression at T2 when controlling for the scores on these constructs at T1. Morningness was not related to any indicators of shift work tolerance at T2 when controlling for shift work tolerance at T1. Flexibility was negatively related to anxiety at T2 when controlling for anxiety at T1. Languidity was positively related to sleepiness and fatigue at T2 when controlling for sleepiness and fatigue at T1. The findings indicate that personality factors, especially hardiness, can predict changes related to shift work tolerance over a period of one year.     

Das Eignungsfeststellungsverfahren für angehende Hauptfachstudierende der Soziologie

This article presents preliminary experience with a selection procedure for the diploma study course in sociology at the LMU Munich, which was first implemented in the winter term 2004/05. Furthermore, it examines the consequences of this procedure. The selection procedure, which is limited in time, was established due to high discontinuation rates and a remarkable congestion of the scientific personnel who are particularly involved in the foundation courses. Judicial fundament of the procedure is an “experimental clause” in the Bavarian University Act. First of all we point out that the number of newly registered undergraduates remarkably declined. Even the total number of applicants is lower than in the years before the initiation of the selection procedure. Secondly, we consider the dwindling during the process of the selection procedure. Contrary to some apprehensions it is obvious that applicants with a good university-entrance diploma do not choose possible alternatives, but still consider the diploma study course in sociology. Concerning the overall evaluation of the selection procedure’s consequences our results show thirdly, that the procedure is highly accepted by all parties concerned and that it therefore has to be regarded as an efficient solution to lower the discontinuation rates as well as to cope with the capacity overload.     

The development of amyloid beta protein deposits in the aged brain

The deposition of amyloid beta protein (Abeta) in the human brain and the generation of neurofibrillary tangles are the histopathological hallmarks of Alzheimer's disease. Accumulation of Abeta takes place in senile plaques and in cerebrovascular deposits as a result of an imbalance between Abeta production and clearance. This Review describes the different types of Abeta deposits, which can be distinguished by their morphology and by the hierarchical involvement of distinct areas of the brain in Abeta deposition. The role of intracellular Abeta in Abeta deposition and the mechanism of Abeta toxicity are also discussed.     

Progression-free survival in oncological clinical studies: Assessment time bias and methods for its correction

Progression-free survival (PFS) is a frequently used endpoint in oncological clinical studies. In case of PFS, potential events are progression and death. Progressions are usually observed delayed as they can be diagnosed not before the next study visit. For this reason potential bias of treatment effect estimates for progression-free survival is a concern. In randomized trials and for relative treatment effects measures like hazard ratios, bias-correcting methods are not necessarily required or have been proposed before. However, less is known on cross-trial comparisons of absolute outcome measures like median survival times. This paper proposes a new method for correcting the assessment time bias of progression-free survival estimates to allow a fair cross-trial comparison of median PFS. Using median PFS for example, the presented method approximates the unknown posterior distribution by a Bayesian approach based on simulations. It is shown that the proposed method leads to a substantial reduction of bias as compared to estimates derived from maximum likelihood or Kaplan–Meier estimates. Bias could be reduced by more than 90% over a broad range of considered situations differing in assessment times and underlying distributions. By coverage probabilities of at least 94% based on the credibility interval of the posterior distribution the resulting parameters hold common confidence levels. In summary, the proposed approach is shown to be useful for a cross-trial comparison of median PFS.     

Leadership coaching,leader role-efficacy,and trust in subordinates. A mixed methods study assessing leadership coaching as a leadership development tool

In this study, we used a two-phase exploratory sequential design consisting of qualitative and quantitative research methods to assess leadership coaching as a leadership development tool. A focus group study combined with a review of theory resulted in hypotheses linking coaching to increased leader role-efficacy (LRE) and leader's trust in subordinates (LTS). Using data from leaders participating in a six month coaching program and a control group, the results showed that LRE and LTS increased in the coaching group, but not in the control group. We also hypothesized that increased trust in subordinates would be related to subordinates' psychological empowerment and turnover intentions. A significant relationship between increased LTS and reduced turnover intentions was found. Finally, we found that the degree of facilitative behavior from the coach positively affected the changes in both leader role-efficacy and trust in subordinates. While the results should be interpreted with caution as the sample is small, our findings support claims that coaching represents a promising leadership development tool. Furthermore, the results regarding trust in subordinates represent contributions to the development of a relational perspective on leadership development.