Testing for a unit root in a stationary ESTAR process

This article develops a statistic for testing the null of a linear unit root process against the alternative of a stationary exponential smooth transition autoregressive model. The asymptotic distribution of the test is shown to be nonstandard but nuisance parameter-free and hence critical values are obtained by simulations. Simulations show that the proposed statistic has considerable power under various data generating scenarios. Applications to real exchange rates also illustrate the ability of our test to reject null of unit root when some of the alternative tests do not.     

A transnational practice between fractured homes: Second-generation Turkish–German migrants’ experiences of visiting and being visited

The paper explores the multiple ways in which visits affect the understanding of home for the Turkish–German second generation who have relocated to Turkey. Based on thematic–narrative analysis of 116 life-story interviews with second-generation ‘returnees’ in five regions of Turkey, three types of visits are identified: (i) family visits to Turkey whilst growing up in Germany; (ii) visits to Germany after the second generation has ‘returned’ to Turkey; (iii) visits to Turkey by the second generation's Germany-residing relatives and friends. Each type has different meanings for the visitors and the visited, creating fluid reflections on the meaning of home, which, especially for the second-generation ‘returnees’, tends to become fractured. Constantly comparing their two home(-land)s since childhood, they often simultaneously feel both ‘here’ and ‘there’ as a result of changing attachments and a mix of positive and negative experiences in both locales with their families, friends and the dominant others.     

An ant colony optimization approach for the proportionate multiprocessor open shop

Multiprocessor open shop makes a generalization to classical open shop by allowing parallel machines for the same task. Scheduling of this shop environment to minimize the makespan is a strongly NP-Hard problem. Despite its wide application areas in industry, the research in the field is still limited. In this paper, the proportionate case is considered where a task requires a fixed processing time independent of the job identity. A novel highly efficient solution representation is developed for the problem. An ant colony optimization model based on this representation is proposed with makespan minimization objective. It carries out a random exploration of the solution space and allows to search for good solution characteristics in a less time-consuming way. The algorithm performs full exploitation of search knowledge, and it successfully incorporates problem knowledge. To increase solution quality, a local exploration approach analogous to a local search, is further employed on the solution constructed. The proposed algorithm is tested over 100 benchmark instances from the literature. It outperforms the current state-of-the-art algorithm both in terms of solution quality and computational time.

     

Technocratic Decision-Making in Times of Crisis? The Use of Data for Scientific Policy Advice in Germany’s COVID-19 Management

Public Organization Review - COVID-19 has demonstrated the importance of data for scientific policy advice. Mechanisms by which data is generated, shared, and ultimately lead to policy responses...     

The Work Profiler: Revision and maintenance of a profiling tool for the recently unemployed in the Netherlands

For the public employment services of many Member countries of the Organisation for Economic Co-operation and Development, the importance of using profiling tools for job seekers is increasing rapidly in importance. With this trend, there is also widening concern about the risks of an over reliance on such tools. Part of the concern lies with a lack of transparency concerning how such tools work. This article aims to address this by offering a detailed investigation of the Work Profiler – the instrument used in the Netherlands by the Institute for Employee Benefits (Uitvoeringsinstituut Werknemersverzekeringen – UWV) to predict re-employment success and provide a diagnosis of key factors hindering job seekers’ return to work. Professionals use these insights to deepen their understanding of the situation of job seekers and decide together with job seekers how to support their return to work. UWV decided to maintain and revise the Work Profiler through a large-scale study involving a sample of 53,238 people. Work Profiler 1.0 was developed in 2007–2010 and has been in use on a regional basis since 2011 and nationwide since 2015. This article explains how the new tool (version 2.0; implemented in 2018) works and, most importantly, demonstrates the choices made to ensure that it functions well and is used effectively by professionals. These latter two aspects are rarely discussed in the literature.     

Testing for the Price- and Wage-Setting Model in Belgium Using Multivariate Cointegration Tests

Using multivariate cointegration tests based on Johansen's approach, this paper tests for the existence of long-run relationships between real wages and other explaining variables in Belgium. We retain two cointegrating vectors which can refer to wage and price setting behaviours.