Algorithmic Analysis of Array-Accessing Programs

For programs whose data variables range over Boolean or finite domains, program verification is decidable, and this forms the basis of recent tools for software model checking. In this paper, we consider algorithmic verification of programs that use Boolean variables, and in addition, access a single array whose length is potentially unbounded, and whose elements range over pairs from Σ × D, where Σ is a finite alphabet and D is a potentially unbounded data domain. We show that the reachability problem, while undecidable in general, is (1) Pspace-complete for programs in which the array-accessing for-loops are not nested, (2) solvable in Ex-pspace for programs with arbitrarily nested loops if array elements range over a finite data domain, and (3) decidable for a restricted class of programs with doubly-nested loops. The third result establishes connections to automata and logics defining languages over data words

Die digitale Vorlesung zur Steigerung der Effektivität und Effizienz des Lernens in Großgruppen

Die Anzahl der Studierenden an deutschen Hochschulen ist in den letzten 10 Jahren um fast 70% gestiegen. So stehen Lehrende an Hochschulen vermehrt dem Problem gegenüber, die Lernumgebung für eine möglichst große Anzahl an Studierenden effektiv und effizient zu gestalten. Im Rahmen eines Innovationsprogrammes für gute Lehre an der Technischen Universität Braunschweig wurde ein neues Lehrkonzept in der Vorlesung Finanzierungstheorie des Instituts für Finanzwirtschaft, basierend auf der „Inverted Classroo“-Methode, implementiert. Ziel dieses Beitrages ist die Erörterung der Frage, ob dieses Lehrkonzept zu einer Steigerung der Effektivität und Effizienz des Lernens in Großgruppen führen kann. (DIPF/Orig.

Political Freedom, External Liberalization and Financial Stability

The chance of financial crises has grown in emerging economies in recent decades. Increasingly, the interest has shifted away from market-based reforms, such as more transparency, towards potentially stabilizing institutions. Among these institutions are better political freedoms, as they could help to foster stronger and more stable domestic demand growth. Using data from the IMF and Freedom House, we test the effectiveness of political freedoms, in particular of civil liberties and political rights, in reducing the chance of banking and currency crises. Our results show that more civil liberties, which are closely linked to worker rights, lower the chance of banking and currency crises, while political rights have no effect on the chance of financial crises. Also, this effect disappears in more open economies, likely due to increased capital mobility.Banking crisis, currency crisis, labor standards, emerging economies,