Zur Exploration statistisch gut angepasster Latent-Class-Modelle durch Homogenitätsanalyse

With this article, an attempt is made to combine both confirmatory and exploratory analysis. It is argued that confirmatory and exploratory approaches have to complement one another. As an example for confirmation latent-class-models are estimated for 3 variables which are supposed to measure a latent dimension “attitudes towards integration — segregation of the mentally ill”. Employing a 3-, and a 4-class solution it can be shown that exclusively looking on the model fit is not sufficient. Since both models fit equally well, both the membership-probabilities and the category-probabilities for each class are inspected. By means of homogeneity-analysis within the latent classes, the interpretation of deviations from the model assumptions is facilitated considerably. It is shown that very special and rare responsepattern may question a straightforward interpretation of a simple parsimonious model.     

The value of a player in n-person games

. The article decomposes the Shapley value into a value matrix which gives the value of every player to every other player in n-person games. Element Φ_ij(v) in the value matrix is positive, zero, or negative, dependent on whether row player i is beneficial, has no impact, or is not beneficial for column player j. The elements in each row and in each column of the value matrix sum up to the Shapley value of the respective player. The value matrix is illustrated by the voting procedure in the European Council of Ministers 1981–1995. Received: 9 September 1998/Accepted: 11 February 2000     

Frame Correction Modelling with Applications to the German Register‐Assisted Census 2011

Frame corrections have been studied in census applications for a long time. One very promising method is dual system estimation, which is based on capture–recapture models. These methods have been applied recently in the USA, England, Israel and Switzerland. In order to gain information on subgroups of the population, structure preserving estimators can be applied [i.e. structure preserving estimation (SPREE) and generalized SPREE]. The present paper extends the SPREE approach with an alternative distance function, the chi‐square. The new method has shown improved estimates in our application with very small domains. A comparative study based on a large‐scale Monte Carlo simulation elaborates on advantages and disadvantages of the estimators in the context of the German register‐assisted Census 2011.     

Effects of data breaches from user-generated content: A corporate reputation analysis

A threat for a growing number of firms in various industries is the occurrence of different breaches of sensitive corporate data. These critical events represent vulnerability for firms' corporate reputations, whose multiple dimensions are affected by customers negative perceptions in various ways. Further, in the Industry 4.0 era, the redundancy of scandals on social media can exacerbate negative effects. This paper reports an investigation into the effects of data breaches on corporate reputation dimensions. In this context, the study conducted latent Dirichlet allocation analysis on social media user-generated content (UGC) for a sample of 35 firms in nine industries that suffered a data breach incident between 2013 and 2016. Incidents have been categorized into three categories: “intentional and internal,” “unintentional and internal,” and “intentional and external” data breaches. The aim of the study was to discover how reputational dimensions changed after these critical events and to identify the differences among the types of data breaches.Results reveal that after critical events, more reputational dimensions appear to be relevant. While before critical events, users typically discuss the “perceived quality” of a firm's offer, after all three types of data breaches, users also pay attention to “customer orientation” and “corporate performance” dimensions. Another key reputation dimension, especially after intentional and internal data breaches, is the “firm as employer,” particularly in the context of a lack of investment in training regarding these events.These findings provide key insights for academics and practitioners to understand large-scale data breaches effects and reputational drawbacks after such incidents.     

Numerical solution of optimal allocation problems in stratified sampling under box constraints

Modern sampling designs in survey statistics, in general, are constructed in order to optimize the accuracy of estimators such as totals, means and proportions. In stratified random sampling a variance minimal solution was introduced by Neyman and Tschuprov. However, practical constraints may lead to limitations of the domain of sampling fractions which have to be considered within the optimization process. Special attention on the complexity of numerical solutions has to be paid in cases with many strata or when the optimal allocation has to be applied repeatedly, such as in iterative solutions of stratification problems. The present article gives an overview of recent numerical algorithms which allow adequate inclusion of box constraints in the numerical optimization process. These box constraints may play an important role in statistical modeling. Furthermore, a new approach through a fixed point iteration with a finite termination property is presented.     

Risk-Based Analysis of the Danish Pork Salmonella Program: Past and Future

The Danish pork Salmonella control program was initiated in 1993 in response to a prominent pork-related outbreak in Copenhagen. It involved improved efforts at slaughter hygiene (postharvest) and on-farm (preharvest) surveillance and control. After 10 years, 95 million Euros, significant reductions in seropositive herds, Salmonella positive carcasses, and pork-attributable human cases (PAHC), questions have arisen about how best to continue this program. The objective of this study was to provide some analysis and information to address these questions. The methods used include a computer simulation model constructed of a series of Excel workbooks, one for each simulated year and scenario ( http://www.ifss.iastate/DanSalmRisk ). Each workbook has three modules representing the key processes affecting risk: seropositive pigs leaving the farm (Production), carcass contamination after slaughter (Slaughter), and PAHC of Salmonella (Attribution). Parameter estimates are derived from an extensive farm-to-fork database collected by industry and government and managed by the Danish Zoonosis Centre ( http://www.food.dtu.dk ). Retrospective (1994–2003) and prospective (2004–2013) simulations were evaluated. The retrospective simulations showed that, except for the first few years (1994–1998), the on-farm program had minimal impact in reducing the number of positive carcasses and PAHC. Most of the reductions in PAHC up to 2003 were, according to this analysis, due to various improvements in abattoir processes. Prospective simulations showed that minimal reductions in human health risk (PAHC) could be achieved with on-farm programs alone. Carcass decontamination was shown as the most effective means of reducing human risk, reducing PAHC to about 10% of the simulated 2004 level.     

The Viability of Career Maturity Theory: A Developmental—Contextual Perspective

The critical role of the timing of person—context interactions is important in the conceptualization of the school-to-work transition. It is argued that career maturity, with its focus on the individual and its ties to stage models and notions of age-appropriateness, gives insufficient attention to the particular contexts of time and culture within which it may be observed. The use of recent advances in developmental theory is suggested as a viable alternative for understanding developmental transitions. Findings from the research literature and from a recent study of young adults from former East Germany and former West Germany are cited in support of this proposal. These findings highlight limitations of the construct of career maturity in showing how individual differences and contextual factors contribute to the school-to-work transition in contrasting environments of former East and West Germany.     

Religion und Bildungserfolg im Migrationskontext – Theoretische Argumente,empirische Befunde und offene Fragen

Religion has received extensive attention as a factor influencing immigrants’ integration. This paper examines the role of religion in explaining ethnic educational inequalities in Germany. Due to a general lack of research in this field, the paper provides an overview of existing empirical findings, specifies theoretical arguments on how religious affiliation, belief and participation possibly affect educational achievement among children of immigrants. Using data from the first wave of the “Children of Immigrants Longitudinal Survey in four European Countries” collected in 2010/11 the paper tests key arguments on the influence of religion on the educational attainment among 14-year-old immigrant and non-immigrant students at German schools. Compared to other religious groups, Muslims display lower rates of educational achievement. However, this can be largely explained by their social background and is independent from their levels of individual religiosity. Interestingly, individual religiosity has a positive effect on the educational achievement among Protestant students, whether with or without a migration background.     

Religion und Gesellschaft – Aktuelle Perspektiven

Increasing public attention to religious questions has in the past years re-invigorated the sociology of religion. As an introduction to the present special issue we outline some institutional and intellectual developments of German language sociology of religion since the post-war period. We furthermore highlight five current trends of the subdiscipline that pertain to the concept of religion, to debates over secularization, to methodological questions of sociological explanation, to interdisciplinary research on religions under conditions of globalization, and to the refinement of quantitative as well as qualitative research methods. Having argued that these trends attest to an increasingly global-comparative approach, we conclude with some research perspectives for future sociology of religion.