Prediction of claims in export credit finance: a comparison of four machine learning techniques

This study evaluates four machine learning (ML) techniques (Decision Trees (DT), Random Forests (RF), Neural Networks (NN) and Probabilistic Neural Networks (PNN)) on their ability to accurately predict export credit insurance claims. Additionally, we compare the performance of the ML techniques against a simple benchmark (BM) heuristic. The analysis is based on the utilisation of a dataset provided by the Berne Union, which is the most comprehensive collection of export credit insurance data and has been used in only two scientific studies so far. All ML techniques performed relatively well in predicting whether or not claims would be incurred, and, with limitations, in predicting the order of magnitude of the claims. No satisfactory results were achieved predicting actual claim ratios. RF performed significantly better than DT, NN and PNN against all prediction tasks, and most reliably carried their validation performance forward to test performance

The decays gluino -> stop_1 b-quark W and gluino -> stop_1 c-quark and phenomenological implications in supersymmetric theories

We show that the decay gluino -> stop_1 b-quark W is important and can even be dominant in the region of parameter space where it is kinematically allowed. We discuss phenomenological implications within the Minimal Supersymmetric Standard Model and models with broken R-parity. We consider the flavour diagonal case as well as a possible mixing between squarks of different generations. In the latter case also the decay gluino -> stop_1 c-quark is potentially important. We show that the decay gluino -> stop_1 b-quark W is sensitive to the stop mixing angle. Furthermore we demonstrate that in scenarios with a higgsino--like LSP the gluino decays mainly into final states containing top quarks or a light stop if allowed by kinematics.Comment: LaTex, 15 pages, 8 figures, uses JHEP3.cls (included), v2, improved discussion of gluino -> stop_1 c-quark, conclusions unchanged, version to appear in JHE

Regulatory Convergence through the Backdoor: TTIP’s Regulatory Cooperation and the Future of Precaution in Europe

This paper analyzes the possible impact of TTIP's so-called regulatory cooperation on the implementation of the precautionary principle in the EU. The European Commission argues that regulatory cooperation will not impinge on the application of the precautionary principle because, first, it does not change the legislative framework of precautionary legislation and, second, the right to regulate will be safeguarded by the TTIPs horizontal chapters. On the contrary, I argue in this paper, that these guarantees are insufficient. Given the methodological and institutional constraints presented by the TTIP's institutional design, in the long run, regulatory cooperation will undermine the precautionary approach to regulation in the EU

Contesting Austerity: On the Limits of EU Knowledge Governance

Lacking robust democratic foundations, EU authority is founded on output legitimacy — delivery of (economic) prosperity through rational governance. Yet current austerity policies are the epitome of irrational governance. While this volume highlights the EU's limited ability to deliver rational output through law and legal rationality, I argue that, without democracy, the EU cannot deliver the desired output through knowledge and technical rationality either. In fact, embedding expert institutions in democratic institutional settings plays a crucial epistemic role, contributing to the production of more reflective, socially inclusive knowledge. Lack of such democratic input in the EU's knowledge production is one of the root causes of its crumbling output legitimacy and the creation of many disenfranchised (internal) peripheries. Three recent challenges of Brexit, TTIP, and austerity may be seen as attempts to reclaim the democratic responsiveness of EU technocratic rule. However, the strategies of exit and voice have not been available in all these cases: in the Greek tragedy, contesting austerity ended in subjugation: a mirror image of ‘rational’ governance if unaided by inclusive democratic process

Imaginaries of Prosperity as Constitutional Imaginaries

This chapter explores the question of what renders imaginaries constitutional. Should we expect to find constitutional imaginaries in constitutional texts and doctrine? Or should we look for them elsewhere in our societies? While constitutional documents or conventions have occupied much of our political imagination, the truly constitutional imaginaries can be only those imaginaries that have actually shaped, or constituted, the ways in which we go about making and re-making our societies. I will argue that the two main constitutional imaginaries of modernity, that is, the social imaginaries that have in fact shaped the deep structure of our societies, have presented themselves as stories of prosperity. These imaginaries of prosperity, through directing individual and collective efforts and resources toward either private or collective routes to prosperity, have shaped the way we think about not only constitutions, but also economy, politics, government, and law. This chapter first explores the relation between social imaginaries and social change, after which it turns to developing the concept of imaginaries of prosperity. Subsequently, it traces the collective imaginary of prosperity behind the Weimar constitution and contrasts it with the privatizing imaginaries of prosperity underlying the European Constitution. The chapter concludes with a reflection on the role of constitutional law and scholarship for social change

CP asymmetries in the supersymmetric trilepton signal at the LHC

In the CP-violating Minimal Supersymmetric Standard Model, we study the production of a neutralino-chargino pair at the LHC. For their decays into three leptons, we analyze CP asymmetries which are sensitive to the CP phases of the neutralino and chargino sector. We present analytical formulas for the entire production and decay process, and identify the CP-violating contributions in the spin correlation terms. This allows us to define the optimal CP asymmetries. We present a detailed numerical analysis of the cross sections, branching ratios, and the CP observables. For light neutralinos, charginos, and squarks, the asymmetries can reach several 10%. We estimate the discovery potential for the LHC to observe CP violation in the trilepton channel.Comment: 39 pages, 8 figures, version to appear in EPJC, discussion(s) added, typo in (D.79), (D.118) corrected, new Fig. 7; The European Physical Journal C, Volume 72, Issue 3, 201

Tau-Sleptons and Tau-Sneutrino in the MSSM with Complex Parameters

We present a phenomenological study of tau-sleptons stau_1,2 and tau-sneutrino in the Minimal Supersymmetric Standard Model with complex parameters A_tau, mu and M_1. We analyse production and decays of stau_1,2 and tau-sneutrino at a future e^+ e^- collider. We present numerical predictions for the important decay rates, paying particular attention to their dependence on the complex parameters. The branching ratios of the fermionic decays of stau_1 and tau-sneutrino show a significant phase dependence for tan(beta) < 10. For tan(beta) > 10 the branching ratios for the stau_2 decays into Higgs bosons depend very sensitively on the phases. We show how information on the phase phi(A_tau) and the other fundamental stau parameters can be obtained from measurements of the stau masses, polarized cross sections and bosonic and fermionic decay branching ratios, for small and large tan(beta) values. We estimate the expected errors for these parameters. Given favorable conditions, the error of A_tau is about 10% to 20%, while the errors of the remaining stau parameters are in the range of approximately 1% to 3%. We also show that the induced electric dipole moment of the tau-lepton is well below the current experimental limit.Comment: LaTex, 25 pages, 11 figures (included); v2: extended discussion on error determination, version to appear in Phys.Rev.