Ein Mixed-Methods-Evaluations-Ansatz zur Untersuchung von Makro-Mikro-Interaktionen

Especially in the case of longitudinal evaluations, mixed-methodological approaches appear to be useful, since the studies are basically suitable for evaluating evaluation objects of a high degree of complexity, such as, for example, dynamic processes in educational structures. Basing on the longitudinal development of professions-related beliefs of mathematics student teachers, this article describes how macro- and microstructures can be taken into account by integrating results obtained through different research methods. With the help of latent growth curve models the development of beliefs of 235 student teachers at five universities could be modeled longitudinally. On the basis of 19 interviews, afterwards interrelationships between institutional frameworks and the individual development of beliefs could be identified on the basis of case studies. Amongst others, a high degree of agreement to constructivist-oriented forms of teaching and learning could be revealed, which can be partly attributed to the experience of university teaching.     

Levelling across the life‐span?: Tracing the face vowel in panel data from the North East of England

Apparent time analysis has revealed that the Tyneside face vowel is the site of two intersecting trends: levelling towards the supra‐northern monophthong as well as the gradual incursion of the southern standard closing diphthong. This article investigates the participation of individual speakers across their life‐span in these ongoing changes in the face vowel. We report on a small‐scale panel sample of six speakers who were recorded in 1971 and again, 42 years later, in 2013. The analysis probes the stability of individual speakers’ grammars, relying on longitudinal ethnographic analysis in the community as well as insights gleaned from sociolinguistic interviews about the speakers’ socio‐demographic trajectory and their presentations of self. The article contributes to the growing body of panel research that aims to determine the scope and the limits of linguistic malleability across speakers’ life histories.     

Effects of resistance training on liver structure and function of aged rats

The aging process may cause negative physiological changes. However, exercises as resistance training (RT) have been considered an important intervention to attenuate these changes. Additionally, liver plays an important role in blood glucose homeostasis in exercise.

Aim: This study aimed to analyze the effects of RT on the liver components of aged animals.

Methods: Male Wistar rats were divided into two groups: 24 months’ group (CONTROL); and group submitted to a progressive RT protocol for 16 weeks (EXERCISE). Both groups were sacrificed at 24 months.

Results: We observed a decrease in blood flow due to the practice of resistance exercises. Besides, our results showed that hepatic tissue plays an important role in glycemic homeostasis during RT. In addition, RT increased mitogen capacity of hepatocytes.

Conclusions: Our study showed many implications for the knowledge about the effects of strength training on old animals’ liver.     

How fields vary

Field theorists have long insisted that research needs to pay attention to the particular properties of each field studied. But while much field‐theoretical research is comparative, either explicitly or implicitly, scholars have only begun to develop the language for describing the dimensions along which fields can be similar to and different from each other. In this context, this paper articulates an agenda for the analysis of variable properties of fields. It discusses variation in the degree but also in the kind of field autonomy. It discusses different dimensions of variation in field structure: fields can be more or less contested, and more or less hierarchical. The structure of symbolic oppositions in a field may take different forms. Lastly, it analyses the dimensions of variation highlighted by research on fields on the sub‐ and transnational scale. Post‐national analysis allows us to ask how fields relate to fields of the same kind on different scales, and how fields relate to fields on the same scale in other national contexts. It allows us to ask about the role resources from other scales play in structuring symbolic oppositions within fields. A more fine‐tuned vocabulary for field variation can help us better describe particular fields and it is a precondition for generating hypotheses about the conditions under which we can expect to observe fields with specified characteristics.     

A general equilibrium analysis of the Laffer argument

This paper examines the Laffer argument (i.e., the possibility that an increase in a tax rate may reduce tax revenues, and vice versa) in a general equilibrium model and using tax reform techniques. Our methodology allows us to examine the Laffer argument in a very general setting. Despite the high level of generality, we are able to reach some clear conclusions that happen to provide some support for the intuition that the Laffer effect requires: (1) a “ high” labour-income tax rate, and (2) a “ large” labour supply response to wage changes. However, the notions of “high” and “large” in our framework are quite different to the interpretations given them in conventional wisdom about the Laffer argument. The analysis also provides indirect support for the intuition that it is not optimal for a government to operate on the downward-sloping segment of the Laffer curve.     

An Integrated Approach to Managing Change

Complex systems often involve a huge number of variables whose interdependence must be taken into account. This makes the adoption of an integrated approach essential for the proper management of a wide range of aspects related to human life, from social matters to the environment. In particular, this paper takes into consideration three different experiences in which the use of an integrated approach represented the most effective response for managing the evolving realities we took into consideration. We focused on the issue of land management, with particular attention to the problem of monoculture in Brazil. Then we analyzed the attempted cooperation between the States of the Aral Sea area for efficient water management of the basin and, finally, we dealt with the matter of energy efficiency and how the production of home integrated systems could lead to a better rationalization of energy consumption in the near future.      

A Structural Analysis of the Effectiveness of Buying Firms' Strategies to Improve Supplier Performance

Many manufacturing firms have increased the amount of component parts and services they outsource, while refocusing on their core capabilities. Outsourcing parts and services to independent, external suppliers means that suppliers' performance is increasingly critical to the long‐term success of these buying firms. Buying firms are increasingly using disparate supplier development strategies to improve supplier performance including supplier assessment, providing incentives for improved performance, instigating competition among suppliers, and direct involvement of the buying firm's personnel with suppliers through activities such as training of suppliers' personnel. Using resource‐based theory, internalization theory, and structural equation modeling, we examine the impact of these supplier development strategies on performance. We conclude that direct involvement activities, where the buying firm internalizes a significant amount of the supplier development effort, play a critical role in performance improvement.     

Children's altruism in public good and dictator experiments

We examine the development of altruistic and free-riding behavior in 6-12 year-old children. We find that the level of altruistic behavior in children is similar to that of adults but that repetition has a different effect. Younger children's contributions of older children, like those of adults, tend to decline. Group attachment is associated with higher contributions. Contributions in a subsequent dictator experiment are correlated with first-round contributions in the public good experiment, but are not strongly correlated with last-round contributions.     

Using mixtures in seemingly unrelated linear regression models with non-normal errors

Seemingly unrelated linear regression models are introduced in which the distribution of the errors is a finite mixture of Gaussian distributions. Identifiability conditions are provided. The score vector and the Hessian matrix are derived. Parameter estimation is performed using the maximum likelihood method and an Expectation–Maximisation algorithm is developed. The usefulness of the proposed methods and a numerical evaluation of their properties are illustrated through the analysis of simulated and real datasets.