Verallgemeinerte DEA-Modelle zur Performanceanalyse

Dyckhoff and Allen derived a generalisation of Data Envelopment Analysis (DEA) in order to measure ecological efficiency. This approach distinguishes between inputs and outputs of an activity on the one hand and their impact on the relevant evaluation criteria—referred to as efforts and benefits—on the other hand. Thereby, the current framework of the DEA for analysing the relative performance of productive units is fundamentally extended. The relevance of this framework is not limited to ecological aspects because many essential problems of DEA application can be solved. Against this background, the paper presents a formalisation of the generalised DEA, applies it to the well-known basic DEA models, and concretises these models for linear effort and benefit functions.     

Multinomial Selection Problem: A Study of BEM and AVC Algorithms

The two well-known and widely used multinomial selection procedures Bechhofor, Elmaghraby, and Morse (BEM) and all vector comparison (AVC) are critically compared in applications related to simulation optimization problems.

Two configurations of population probability distributions in which the best system has the greatest probability p _i of yielding the largest value of the performance measure and has or does not have the largest expected performance measure were studied.

The numbers achieved by our simulations clearly show that none of the studied procedures outperform the other in all situations. The user must take into consideration the complexity of the simulations and the performance measure probability distribution properties when deciding which procedure to employ.

An important discovery was that the AVC does not work in populations in which the best system has the greatest probability p _i of yielding the largest value of the performance measure but does not have the largest expected performance measure.     

Looking Too Old? How an Older Age Appearance Reduces Chances of Being Hired

Building on theories of impression formation based on faces, this research investigates the impact of job candidates’ facial age appearance on hiring as well as the underlying mechanism. In an experiment, participants decided whether to hire a fictitious candidate aged 50 years, 30 years or without age information. The candidate's age was signalled either via chronological information (varied by date of birth) or via facial age appearance (varied by a photograph on the résumé). Findings showed that candidates with older‐appearing faces – but not chronologically older candidates – triggered impressions of low health and fitness, compared to younger‐appearing candidates. These impressions reduced perceptions of person–job fit, which lowered hiring probabilities for older‐appearing candidates. These findings provide the first evidence that trait impressions from faces are a determinant of age discrimination in personnel selection. They call for an extension of current models of age discrimination by integrating the effects of face‐based trait impressions, particularly with respect to health and fitness.     

Politics of childhood,childrens rights,and intergenerational relations

One of the more decisive questions in the discussion of human living conditions, which then also produces the most diverse answers, concerns the relation between violence and civilization. In this context the treatment of childhood and of childrens rights is a crucial issue of this century. We live in a period of socialism, the womens movement, intercourse, individualism. Are we not entering the period of youth? (Benjamin 1991, p. 9), asked Walter Benjamin 80 years ago, shortly after Ellen Key had program-matically declared The Century of the Child (Key 1978). Aries, in his history of childhood and family life in the Ancien Regime, investigated the generalization of social control and subsequent new forms of intervention into social relations (Aries 1978, pp. 556–8). They concern:     

Designing a non-inferiority study in kidney transplantation: a case study

In organ transplantation, placebo-controlled clinical trials are not possible for ethical reasons, and hence non-inferiority trials are used to evaluate new drugs. Patients with a transplanted kidney typically receive three to four immunosuppressant drugs to prevent organ rejection. In the described case of a non-inferiority trial for one of these immunosuppressants, the dose is changed, and another is replaced by an investigational drug. This test regimen is compared with the active control regimen. Justification for the non-inferiority margin is challenging as the putative placebo has never been studied in a clinical trial. We propose the use of a random-effect meta-regression, where each immunosuppressant component of the regimen enters as a covariate. This allows us to make inference on the difference between the putative placebo and the active control. From this, various methods can then be used to derive the non-inferiority margin. A hybrid of the 95/95 and synthesis approach is suggested. Data from 51 trials with a total of 17,002 patients were used in the meta-regression. Our approach was motivated by a recent large confirmatory trial in kidney transplantation. The results and the methodological documents of this evaluation were submitted to the Food and Drug Administration. The Food and Drug Administration accepted our proposed non-inferiority margin and our rationale.     

A note on multivariate linear regression

In this note, a hypothesis test based on relevant statistical differences is proposed for multivariate linear regression models whose design matrix rank does not equal the number of regression variables. A statistical example is also provided to illustrate the proposed hypothesis test.