Modeling heterogeneity in ranked responses by nonparametric maximum likelihood:How do Europeans get their scientific knowledge?

This paper is motivated by a Eurobarometer survey on science knowledge. As part of the survey, respondents were asked to rank sources of science information in order of importance. The official statistical analysis of these data however failed to use the complete ranking information. We instead propose a method which treats ranked data as a set of paired comparisons which places the problem in the standard framework of generalized linear models and also allows respondent covariates to be incorporated. An extension is proposed to allow for heterogeneity in the ranked responses. The resulting model uses a nonparametric formulation of the random effects structure, fitted using the EM algorithm. Each mass point is multivalued, with a parameter for each item. The resultant model is equivalent to a covariate latent class model, where the latent class profiles are provided by the mass point components and the covariates act on the class profiles. This provides an alternative interpretation of the fitted model. The approach is also suitable for paired comparison data

WOLFGANG AMADEUS MOZART: SMRT GENIJA

The early and unexpected death of Wolfgang Amadeus Mozart (Salzburg, 1756 – Vienna, 1791) was a mystery from the very first day and the subject of wildest speculations and adventurous assertions. Over the last 100 years, medical science has investigated the physical sufferings and the mysterious death of Mozart with increasing intensity. The aim of this article was to recreate Mozart’s pathography relying on the his correspondence with father Leopold and sister Nannerl and on reports from his physicians and contemporaries. The rumour that Mozart was poisoned followed shortly after his death on 5 December 1791, at the age of 35, and has survived to this day. The alleged culprits were his physician van Swieten, Mozart’s freemasons lodge, and the Imperial Chapel Master Salieri. Mozart however died of chronic kidney disease and ultimately of uraemia. If kidney damage reaches a critical point, even a minimum additional stress can lead to its failure. This usually occurs in the fourth decade of life. Next time we listen to Mozart, we should remember that this apparently happy person was actually a precocious boy, ripped of his childhood, whose short life was an endless chain of complaints, fatigue, misery, concern, and malady.Rana i neočekivana smrt Wolfganga Amadeusa Mozarta (r. u Salzburgu 1756. – u. u Beču 1791.) obavijena je tajnom od prvoga dana te je postala predmetom nevjerojatnih nagađanja i hrabrih tvrdnji. Medicinska je znanost u posljednjih stotinu godina sa sve više interesa istraživala Mozartove tjelesne tegobe i tajanstvenu smrt. Želja je ovoga članka rekonstruirati Mozartovu patografiju osalanjajući se na njegovu korespondenciju s ocem Leopoldom i sestrom Nannerl te na izjave njegovih liječnika i suvremenika. Ubrzo nakon Mozartove smrti 5. prosinca 1791., u dobi od 35 godina, raširila se glasina da je otrovan, koja je i danas aktualna. Navodni osumnjičenici su njegov osobni liječnik van Swieten, Mozartova slobodnozidarska loža te dvorski skladatelj Antonio Salieri. Ipak, Mozart je umro od uremije uslijed kronične bolesti bubrega. Kada oštećenje bubrega dosegne kritičnu točku, dovoljan je i neznatan stres koji će dovesti do njegova zatajenja. To se obično događa u četrdesetim godinama života. Sljedeći put kada budemo slušali Mozartovu glazbu, sjetit ćemo se da je ova naizgled sretna osoba zapravo bilo prerano sazrijelo dijete kojemu je ukradeno djetinjstvo i čiji je život bio beskonačan niz tegoba, premorenosti, jada, briga i bolesti

Modelling dependency in multivariate paired comparisons:a log-linear approach.

A log-linear representation of the Bradley-Terry model is presented for multivariate paired comparison data, where judges are asked to compare pairs of objects on more than one attribute. By converting such data to multiple binomial responses, dependencies between the decisions of the judges as well as possible association structures between the attributes can be incorporated in the model, providing an advantage over parallel univariate analyses of individual attributes. The approach outlined gives parameters which can be interpreted as (conditional) log–odds and log–odds ratios. As the model is a generalised linear model, parameter estimation can use standard software and the GLM framework can be used to test hypotheses on these parameters

The Rasch Sampler

The Rasch sampler is an efficient algorithm to sample binary matrices with given marginal sums. It is a Markov chain Monte Carlo (MCMC) algorithm. The program can handle matrices of up to 1024 rows and 64 columns. A special option allows to sample square matrices with given marginals and fixed main diagonal, a problem prominent in social network analysis. In all cases the stationary distribution is uniform. The user has control on the serial dependency.

A Microanalytical Simulation Model to Predict the Long-Term Evolution of Employment Biographies in Austria: The Demographics Module

The well-known problems of decreasing birth rates and population ageing represent a major challenge for the Austrian pension system. It is expected that the group of pensioners will grow steadily in the future, while the proportion of people that support them - the taxpayers - will shrink. In this regard, microsimulation provides a valuable tool to identify the impact of various policy measures. With microsimulation, it is not only possible to predict cross-sectional data (e.g., the distribution of age groups in 2050), but also to simulate lifecourses of people, providing longitudinal outcomes. The demographics module is the first in a series of modules that are part of a microsimulation prototype. This prototype is being developed in order to predict the long-term evolution of Employment Biographies in Austria

prefmod: An R Package for Modeling Preferences Based on Paired Comparisons, Rankings, or Ratings

The first part of this paper describes a series of loglinear preference models based on paired comparisons, a method of measurement whose aim is to order a set of objects according to an attribute of interest by asking subjects to compare pairs of objects. Based on the basic Bradley-Terry specification, two types of models, the loglinear Bradley-Terry model and a pattern approach are presented. Both methods are extended to include subject and object-specific covariates and some further structural effects. In addition, models for derived paired comparisons (based on rankings and ratings) are also included. Latent classes and missing values can be included. The second part of the paper describes the package prefmod that implements the above models in R. Illustrational applications are provided in the last part of the paper

The Rasch Sampler

The Rasch sampler is an efficient algorithm to sample binary matrices with given marginal sums. It is a Markov chain Monte Carlo (MCMC) algorithm. The program can handle matrices of up to 1024 rows and 64 columns. A special option allows to sample square matrices with given marginals and fixed main diagonal, a problem prominent in social network analysis. In all cases the stationary distribution is uniform. The user has control on the serial dependency. (authors' abstract

REM sleep is related to the transfer of implicit procedural knowledge following metacognitive learning

Objective: The hypothesis that REM sleep is also related to the transfer of implicit procedural knowledge was tested. Methods: A total of 21female adults (mean age: 19.49years) took part in the study. After a baseline night, participants were randomly assigned to one of two conditions to solve a cognitive procedural task (Tower of Hanoi problem; ToH); on the evening of the assessment night, one group solved the cognitive procedural task with and one group solved the task without metacognitive stimulation. The morning after the assessment night, participants solved three further transfer tasks (ToH with more disks; the Hobbits and Orcs problem; Katona's card problem). Results: Participants with metacognitive stimulation showed an increased performance in all three transfer tasks. Moreover, these participants had a significantly increased REM sleep. Conclusion: REM sleep seems to be related to metacognitively acquired implicit procedural knowledge. The transfer of the acquired implicit procedural knowledge does not seem to be limited to structurally similar task

Adolescents' self-reported sleep quantity and sleep-related personality traits—A pilot study

Summary: Question of the study: The aim of this pilot study was to assess adolescents' self-reported sleep quantity and personality traits in order to describe typical personality patterns related to sleep and characteristics that distinguish between good and poor sleepers. Participants and methods: A total of 134 adolescents (mean age: 18.60; 74 females and 60 males) completed a single sleep-related personality traits questionnaire (FEPS-I) and daily sleep logs for seven consecutive days. The daily logs data were used to cluster participants in three subgroups of poor, normal, and good sleep quality. Results: Up to 25 % of the adolescents could be considered ‘poor' sleepers and displayed personality traits such as decreased self-confidence, increased mental arousal, and self-perception of body sensations. Female adolescents were at high risk of being ‘poor' sleepers, yet up to 20 % of the adolescents could be described as ‘good' sleepers. Fifty-five per cent of the adolescents could be considered ‘normal' sleepers without appropriate sleep-related personality traits or sleeping habits. Conclusions: The pilot project, using exclusively self-reported sleep data, showed that about a quarter of adolescents were considered ‘poor' sleepers with specific sleep-related personality traits. Further investigations are needed to support these results and to allow possible preventive intervention