Nonparametric estimation in the illness-death model using prevalent data

We study nonparametric estimation of the illness-death model using left-truncated and right-censored data. The general aim is to estimate the multivariate distribution of a progressive multi-state process. Maximum likelihood estimation under censoring suffers from problems of uniqueness and consistency, so instead we review and extend methods that are based on inverse probability weighting. For univariate left-truncated and right-censored data, nonparametric maximum likelihood estimation can be considerably improved when exploiting knowledge on the truncation distribution. We aim to examine the gain in using such knowledge for inverse probability weighting estimators in the illness-death framework. Additionally, we compare the weights that use truncation variables with the weights that integrate them out, showing, by simulation, that the latter performs more stably and efficiently. We apply the methods to intensive care units data collected in a cross-sectional design, and discuss how the estimators can be easily modified to more general multi-state models.     

Emigration of Poles to the United Kingdom: history,present state and future prospects

The history of Polish immigration within the United Kingdom is several centuries old. Yet never in its history was such a mass migration as that after the Polish accession to the EU in 2004. During the over ten years that followed, almost a million Poles chose to settle in the United Kingdom. This article reviews and analyses past and present Polish emigration to the United Kingdom. It provides answers to questions regarding who the Polish immigrants are, what work they perform and how they have integrated within British society. It also considers the factors that have influenced the future dynamics of migration from Poland. Based on these, we have formed the hypothesis that while the years of 2004‐2016 saw, statistically, the largest emigration from Poland to the United Kingdom in recorded history, in the future, the number of Polish expatriates living in the United Kingdom will drop or at least the number of newcomers will decrease.     

Recoverable robust spanning tree problem under interval uncertainty representations

This paper deals with the recoverable robust spanning tree problem under interval uncertainty representations. A strongly polynomial time, combinatorial algorithm for the recoverable spanning tree problem is first constructed. This problem generalizes the incremental spanning tree problem, previously discussed in literature. The algorithm built is then applied to solve the recoverable robust spanning tree problem, under the traditional interval uncertainty representation, in polynomial time. Moreover, the algorithm allows to obtain several approximation results for the recoverable robust spanning tree problem under the Bertsimas and Sim interval uncertainty representation and the interval uncertainty representation with a budget constraint.     

Why practitioners do (not) apply crisis communication theory in practice

Twenty-five in-depth interviews with Belgian crisis communication practitioners were conducted to examine the gap between theory and practice. Crisis communication has become an important research area within public relations. Several studies have resulted in theories and guidelines regarding the effective use of communication during organizational crises. Unfortunately, these findings are not always put into practice. This study examines to what extent public relations practitioners apply theory in practice during crises and why. The findings offer an opportunity to formulate potential ways in which we can bridge the scholar-practitioner divide in public relations, through guidelines for both scholars and practitioners.     

Developing intercultural competence of teachers of English as a foreign language through an international project

This paper reports an international project which took place at Nicolaus Copernicus University, where students and teachers from four European universities met for a two-week summer school. The main objective was to develop intercultural competence of teachers of English as a foreign language and their ability to demonstrate this skill during an English lesson. The paper depicts the tools implemented in the project and shows how they affected the learning outcomes by presenting the students’ and teachers’ perspectives.     

A Euclidean Likelihood Estimator for Bivariate Tail Dependence

The spectral measure plays a key role in the statistical modeling of multivariate extremes. Estimation of the spectral measure is a complex issue, given the need to obey a certain moment condition. We propose a Euclidean likelihood-based estimator for the spectral measure which is simple and explicitly defined, with its expression being free of Lagrange multipliers. Our estimator is shown to have the same limit distribution as the maximum empirical likelihood estimator of Einmahl and Segers (2009 Einmahl , J. H. J. , Segers , J. ( 2009 ). Maximum empirical likelihood estimation of the spectral measure of an extreme-value distribution . Ann. Statist. 37 ( 5B ): 2953 – 2989 .[Crossref], [Web of Science ®] , [Google Scholar]). Numerical experiments suggest an overall good performance and identical behavior to the maximum empirical likelihood estimator. We illustrate the method in an extreme temperature data analysis.