Die Transformation der Jugendhilfe in Ostdeutschland im Kontext von Tradition, Diskontinuität und Strukturbildung

Changes in the child care legislation in 1990 led to the development of a new helping culture both in West and East Germany at the same time. Paternalistic relations to the clients had to be replaced by autonomy focused and thus professional interaction patterns. So clients were involved in the process of choosing adequate educational support. By comparing two East German youth welfare agencies we show the factors that impede the process of restructuring an appropriate professional-client relationship. The most important factor is the fallacy of mistaking educational support for education itself.     

Understanding Mechanisms Underlying Peer Effects: Evidence From a Field Experiment on Financial Decisions

Using a high‐stakes field experiment conducted with a financial brokerage, we implement a novel design to separately identify two channels of social influence in financial decisions, both widely studied theoretically. When someone purchases an asset, his peers may also want to purchase it, both because they learn from his choice (“social learning”) and because his possession of the asset directly affects others' utility of owning the same asset (“social utility”). We randomize whether one member of a peer pair who chose to purchase an asset has that choice implemented, thus randomizing his ability to possess the asset. Then, we randomize whether the second member of the pair: (i) receives no information about the first member, or (ii) is informed of the first member's desire to purchase the asset and the result of the randomization that determined possession. This allows us to estimate the effects of learning plus possession, and learning alone, relative to a (no information) control group. We find that both social learning and social utility channels have statistically and economically significant effects on investment decisions. Evidence from a follow‐up survey reveals that social learning effects are greatest when the first (second) investor is financially sophisticated (financially unsophisticated); investors report updating their beliefs about asset quality after learning about their peer's revealed preference; and, they report motivations consistent with “keeping up with the Joneses” when learning about their peer's possession of the asset. These results can help shed light on the mechanisms underlying herding behavior in financial markets and peer effects in consumption and investment decisions.     

Definition and aggregation of a performance measurement system in three aeronautical workshops using the ECOGRAI method

The requirement for a performance measurement system is essential in order to know the status of the production system and then to improve its control. Focused on research on the control of production systems for 20 years with the development of GRAI methodology, the LAPS/GRAI of University Bordeaux 1 worked for more than 10 years on the definition and the implementation of performance indicator systems through the development of ECOGRAI method and on the aggregation of performance. This paper presents an application of the ECOGRAI method to a workshop inside an aeronautical subcontracting company close to Bordeaux. The first part of the paper will be dedicated to a short presentation of the ECOGRAI method. In particular, we will present six phases of the structured approach and the main tools which are used in the method: the GRAI grid, the coherence panel and the specification sheet and the identity card of the indicators. In the second part, we will present a test case. First, we will present the context of the test case and the objectives that we had to meet. Then we will present the models of the control system and of the physical system through the GRAI grid and actigrams. We will show how we proposed to model the global control of the company and the detailed control of each workshop. Then, we will focus particularly on the way we have identified the performance indicators, based on the objectives and decision variables of the GRAI grid. We will also show how we solved the problem of aggregation of performance in relation to the coordination of decision-making. In the third part, we will detail how we ensured that these indicators were adapted to the control of the workshop and how we ensured their consistency. Finally, we will show to what extent the implementation of the coherent performance indicator system had an impact on the organization and the running of the workshop.     

Noncrossing structured additive multiple-output Bayesian quantile regression models

Quantile regression models are a powerful tool for studying different points of the conditional distribution of univariate response variables. Their multivariate counterpart extension though is not straightforward, starting with the definition of multivariate quantiles. We propose here a flexible Bayesian quantile regression model when the response variable is multivariate, where we are able to define a structured additive framework for all predictor variables. We build on previous ideas considering a directional approach to define the quantiles of a response variable with multiple outputs, and we define noncrossing quantiles in every directional quantile model. We define a Markov chain Monte Carlo (MCMC) procedure for model estimation, where the noncrossing property is obtained considering a Gaussian process design to model the correlation between several quantile regression models. We illustrate the results of these models using two datasets: one on dimensions of inequality in the population, such as income and health; the second on scores of students in the Brazilian High School National Exam, considering three dimensions for the response variable.     

Chronic pain,pain severity and analgesia use in Australian women of reproductive age

Background

The increasing prevalence and adverse outcomes associated with opioid analgesia use in women of reproductive age have become a significant public health issue internationally, with use during pregnancy potentially affecting maternal and infant health outcomes.

Effects of international student exchange on pre-service teachers: a quasi-experimental study

This contribution provides empirical answers to the question of how teaching-specific competencies develop during participation in an international student exchange programme. The quantitative analyses of this quasi-experimental study suggest that, generally speaking, no specific developments occur during an exchange experience. These findings contradict the majority of existing literature. Possible reasons for this divergence are discussed. The interpretation of the results suggests future research should focus on the key question of pre-conditions for productive exchange experiences.     

On testing for independence between the innovations of several time series

Test statistics for checking the independence between the innovations of several time series are developed. The time series models considered allow for general specifications for the conditional mean and variance functions that could depend on common explanatory variables. In testing for independence between more than two time series, checking pairwise independence does not lead to consistent procedures. Thus a finite family of empirical processes relying on multivariate lagged residuals are constructed, and we derive their asymptotic distributions. In order to obtain simple asymptotic covariance structures, Möbius transformations of the empirical processes are studied, and simplifications occur. Under the null hypothesis of independence, we show that these transformed processes are asymptotically Gaussian, independent, and with tractable covariance functions not depending on the estimated parameters. Various procedures are discussed, including Cramér–von Mises test statistics and tests based on non‐parametric measures. The ranks of the residuals are considered in the new methods, giving test statistics which are asymptotically margin‐free. Generalized cross‐correlations are introduced, extending the concept of cross‐correlation to an arbitrary number of time series; portmanteau procedures based on them are discussed. In order to detect the dependence visually, graphical devices are proposed. Simulations are conducted to explore the finite sample properties of the methodology, which is found to be powerful against various types of alternatives when the independence is tested between two and three time series. An application is considered, using the daily log‐returns of Apple, Intel and Hewlett‐Packard traded on the Nasdaq financial market. The Canadian Journal of Statistics 40: 447–479; 2012 © 2012 Statistical Society of Canada