University of Mannheim

About: University of Mannheim is a education organization based out in Mannheim, Germany. It is known for research contribution in the topics: Context (language use) & Politics. The organization has 4448 authors who have published 12918 publications receiving 446557 citations. The organization is also known as: Uni Mannheim & UMA.

Governments, Informal Links to Militias, and Accountability

Abstract: From Syria to Sudan, governments have informal ties with militias that use violence against opposition groups and civilians. Building on research that suggests these groups offer governments logistical benefits in civil wars as well as political benefits in the form of reduced liability for violence, we provide the first systematic global analysis of the scale and patterns of these informal linkages. We find over 200 informal state–militia relationships across the globe, within but also outside of civil wars. We illustrate how informal delegation of violence to these groups can help some governments avoid accountability for violence and repression. Our empirical analysis finds that weak democracies as well as recipients of financial aid from democracies are particularly likely to form informal ties with militias. This relationship is strengthened as the monitoring costs of democratic donors increase. Out-of-sample predictions illustrate the usefulness of our approach that views informal ties to militias as deliberate government strategy to avoid accountability.

Inequality Constraints in the Fractionally Integrated GARCH Model

Abstract: In this article we derive necessary and sufficient conditions for the nonnegativity of the conditional variance in the fractionally integrated generalized autoregressive conditional heteroskedastic (p, d, q) (FIGARCH) model of the order p � 2a nd sufficient conditions for the general model. These conditions can be seen as being analogous to those derived by Nelson and Cao (1992, Journal of Business & Economic Statistics 10, 229–235) for the GARCH(p, q) model. However, the inequality constraints which we derive for the FIGARCH model illustrate two remarkable properties of the FIGARCH model which are in contrast to the GARCH model: (i) even if all parameters are nonnegative, the conditional variance can become negative and (ii) even if all parameters are negative (apart from d), the conditional variance can be nonnegative almost surely. In particular, the conditions for the (1, d, 1) model substantially enlarge the sufficient parameter set provided by Bollerslev and Mikkelsen (1996, Journal of Econometrics 73, 151–184). The importance of the result is illustrated in an empirical application of the FIGARCH(1, d, 1) model to Japanese yen versus U.S. dollar exchange rate data.

Addiction Research Consortium: Losing and regaining control over drug intake (ReCoDe)-From trajectories to mechanisms and interventions.

Abstract: One of the major risk factors for global death and disability is alcohol, tobacco, and illicit drug use. While there is increasing knowledge with respect to individual factors promoting the initiation and maintenance of substance use disorders (SUDs), disease trajectories involved in losing and regaining control over drug intake (ReCoDe) are still not well described. Our newly formed German Collaborative Research Centre (CRC) on ReCoDe has an interdisciplinary approach funded by the German Research Foundation (DFG) with a 12-year perspective. The main goals of our research consortium are (i) to identify triggers and modifying factors that longitudinally modulate the trajectories of losing and regaining control over drug consumption in real life, (ii) to study underlying behavioral, cognitive, and neurobiological mechanisms, and (iii) to implicate mechanism-based interventions. These goals will be achieved by: (i) using mobile health (m-health) tools to longitudinally monitor the effects of triggers (drug cues, stressors, and priming doses) and modify factors (eg, age, gender, physical activity, and cognitive control) on drug consumption patterns in real-life conditions and in animal models of addiction; (ii) the identification and computational modeling of key mechanisms mediating the effects of such triggers and modifying factors on goal-directed, habitual, and compulsive aspects of behavior from human studies and animal models; and (iii) developing and testing interventions that specifically target the underlying mechanisms for regaining control over drug intake.

What can go wrong will go wrong: Birthday effects and early tracking in the German school system

Abstract: At the age of ten German pupils are given a secondary school track recommendation which largely determines the actual track choice. Track choice has major effects on the life course, mainly through labor market outcomes. Using data from the German PISA extension study, we analyze the effect of month of birth and thus relative age on such recommendations. We find that younger pupils are less often recommended to and actually attend Gymnasium, the most attractive track in terms of later life outcomes. Flexible enrolment and grade retention partly offset these inequalities and the relative age effect dissipates as students age.

A Report on the Complex Word Identification Shared Task 2018

Abstract: We report the findings of the second Complex Word Identification (CWI) shared task organized as part of the BEA workshop co-located with NAACL-HLT’2018. The second CWI shared task featured multilingual and multi-genre datasets divided into four tracks: English monolingual, German monolingual, Spanish monolingual, and a multilingual track with a French test set, and two tasks: binary classification and probabilistic classification. A total of 12 teams submitted their results in different task/track combinations and 11 of them wrote system description papers that are referred to in this report and appear in the BEA workshop proceedings.