Ausgelernt? Professor/innen im Prozess der Professionalisierung

Do university teachers have finished to learn, when they are hired for a position as full professor? That seems to be false, if you look at knowledge enrichment by research as learning. For Teaching and management it seems more justified. Factually full professors very seldom participate at corresponding continuing education or consulting. Learning takes place mostly on the side as learning by doing. Professionalization in a full sense however is only realized, if competences are developed also in these fields. As corresponding learning can be supported by continuous education and consulting is a very important task of academic personnel development.     

Elitenselektion durch Bildung oder durch Herkunft?

Does the social origin have a direct effect on the unequal recruitment of the German business elites? Or, does the social origin have an indirect effect on the unequal recruitment only, by means of the unequal participation in the educational system as suggested by the functionalist elite theory? This question is examined with special reference to the business elite. For the 6.500 engineers, jurists, and economists, who received a doctor’s degree in the years of 1955, 1965, 1975, and 1985, the correlation between social origin, educational career, and professional career is analyzed by multivariate methods. The chances of achieving an executive position are 50% higher for individuals with a service class I background and 100% higher for those individuals with an upper class background in contrast to individuals with working class and middle class background. Therefore, the functionalist view can be regarded as incorrect. On the contrary, it holds that social origin has a strong direct effect on the social selection of the elites. Consequently, the social opening of the German educational system did not result into a social opening of the recruitment practices of the business elite. Rather, the opposite is the case: Social selection increased for the 1975 and 1985 cohorts.     

A tutorial on adaptive MCMC

We review adaptive Markov chain Monte Carlo algorithms (MCMC) as a mean to optimise their performance. Using simple toy examples we review their theoretical underpinnings, and in particular show why adaptive MCMC algorithms might fail when some fundamental properties are not satisfied. This leads to guidelines concerning the design of correct algorithms. We then review criteria and the useful framework of stochastic approximation, which allows one to systematically optimise generally used criteria, but also analyse the properties of adaptive MCMC algorithms. We then propose a series of novel adaptive algorithms which prove to be robust and reliable in practice. These algorithms are applied to artificial and high dimensional scenarios, but also to the classic mine disaster dataset inference problem.     

Mood in Daily Contexts: Relationship With Risk in Early Adolescence

Disturbances in affect have been linked to problem behavior in adolescence and future psychopathology, but little is known about how such disturbances manifest themselves in everyday contexts. This study investigated daily mood in Dutch 7th graders, aged 11–14. Cluster analysis of problem measures distinguished high-risk (n=25) and low-risk (n=106) subgroups. Participants completed experience-sampling reports of mood, social context, and location nine times daily for 5 days. Multilevel regression analyses of four mood measures confirmed higher anxiety and depressed mood in the high-risk group. Moods varied by location and social context, with significant differences between groups in two specific social contexts. First, when with family, low-risk adolescents felt less depressed than when alone, whereas high-risk adolescents felt more depressed. Second, high-risk adolescents showed more pronounced anxiety in social situations outside the network of family and friends. These findings point to everyday social contexts in which young adolescents with emotional and behavioral problems appear to be particularly vulnerable.     

OUTSOURCING WHEN INVESTMENTS ARE SPECIFIC AND INTERRELATED

Using the universe of large Canadian manufacturing firms in 1988 and 1996, we investigate to what extent outsourcing patterns concord with the predictions of a simple property rights model. The unique availability of disaggregate information on outputs as well as inputs permits the construction of a detailed measure of vertical integration. We rely on five measures of technological intensity to proxy for investments that are likely to be specific to a buyer–seller relationship. A theoretical model that allows for varying degrees of investment specificity and interrelatedness—externalities between buyer and supplier investments—guides the analysis. Property rights predictions on the link between investment intensities and optimal ownership are strongly supported, but only for transactions with low interrelatedness. High specificity and low risk of appropriation strengthen the predictions in the model and in the data.     

A 14-h night-shift in the control room of a fire brigade

All 29 operators in the control room of a fire brigade performed test sessions during work and leisure time at 2-h intervals on a day with a 14-h night-shift, a day off and a day with a 10-h morning shift. The test sessions consisted of a visual search choice reaction time test and two Sternberg memory search tests (1 or 5 letters had to be memorized). Furthermore, the operators recorded their oral temperature and their subjective alertness before each test session. The subject also kept a diary of work and sleep times for 14 days. The circadian rhythm of body temperature was hardly changed by a single night-shift. Parallel to the body temperature, the subjective alertness fell significantly during the night-shift reaching a minimum value at 06:00 h. The mean reaction times increased non-significantly at the end of the night-shift and the results of the two Sternberg memory search tests showed no significant trends. The sleep of the operators after the night-shift was on average reduced to 5 hs 34 min. The results of subjective rating of alertness and reaction time test are interpreted as effects of the combined influences of circadian rhythmicity, sleep loss and time on professional task. Most results support the conclusion that a 14-h night-shift without extensive breaks is not acceptable.     

An upper bound on the total restrained domination number of a tree

Let G=(V,E) be a graph. A set of vertices S?V is a total restrained dominating set if every vertex is adjacent to a vertex in S and every vertex of $V-\nobreak S$ is adjacent to a vertex in V?S. The total restrained domination number of G, denoted by γ _tr (G), is the smallest cardinality of a total restrained dominating set of G. A support vertex of a graph is a vertex of degree at least two which is adjacent to a leaf. We show that $\gamma_{\mathit{tr}}(T)\leq\lfloor\frac{n+2s+\ell-1}{2}\rfloor$ where T is a tree of order n≥3, and s and ? are, respectively, the number of support vertices and leaves of T. We also constructively characterize the trees attaining the aforementioned bound.     

Median problems with positive and negative weights on cycles and cacti

This paper deals with facility location problems on graphs with positive and negative vertex weights. We consider two different objective functions: In the first one (MWD) vertices with positive weight are assigned to the closest facility, whereas vertices with negative weight are assigned to the farthest facility. In the second one (WMD) all the vertices are assigned to the nearest facility. For the MWD model it is shown that there exists a finite set of points in the graph which contains the locations of facilities in an optimal solution. Furthermore, algorithms for both models for the 2-median problem on a cycle are developed. The algorithm for the MWD model runs in linear time, whereas the algorithm for the WMD model has a time complexity of  O(n²)\mathcal{O}(n^{2}) .