Refine
Year of publication
Document Type
- Report (471) (remove)
Language
- English (471) (remove)
Has Fulltext
- yes (471)
Is part of the Bibliography
- no (471)
Keywords
- islamic state (13)
- terrorism (13)
- IS (9)
- Egypt (8)
- Syria (8)
- islamism (7)
- Europe (6)
- Germany (6)
- Goethe, Johann Wolfgang von (6)
- USA (6)
Institute
- Gesellschaftswissenschaften (212)
- Exzellenzcluster Die Herausbildung normativer Ordnungen (112)
- Wirtschaftswissenschaften (96)
- Center for Financial Studies (CFS) (42)
- House of Finance (HoF) (30)
- Sustainable Architecture for Finance in Europe (SAFE) (30)
- Informatik (20)
- Mathematik (16)
- Extern (8)
- Physik (7)
Tractable hedging - an implementation of robust hedging strategies : [This Version: March 30, 2004]
(2004)
This paper provides a theoretical and numerical analysis of robust hedging strategies in diffusion–type models including stochastic volatility models. A robust hedging strategy avoids any losses as long as the realised volatility stays within a given interval. We focus on the effects of restricting the set of admissible strategies to tractable strategies which are defined as the sum over Gaussian strategies. Although a trivial Gaussian hedge is either not robust or prohibitively expensive, this is not the case for the cheapest tractable robust hedge which consists of two Gaussian hedges for one long and one short position in convex claims which have to be chosen optimally.
This paper analyzes the equilibrium pricing implications of contagion risk in a two-tree Lucas economy with CRRA preferences. The dividends of both trees are subject to downward jumps. Some of these jumps are contagious and increase the risk of subsequent jumps in both trees for some time interval. We show that contagion risk leads to large price-dividend ratios for small assets, a joint movement of prices in the case of a regime change from the calm to the contagion state, significantly positive correlations between assets, and large positive betas for small assets. Whereas disparities between the assets with respect to their propensity to trigger contagion barely matter for pricing, the prices of robust assets that are hardly affected by contagion and excitable assets that are severely hit by contagion differ significantly. Both in absolute terms and relatively to the market, the price of a small safe haven increases if the economy reaches the contagion state. On the contrary, the price of a small, contagion-sensitive asset exhibits a pronounced downward jump.
An analysis of the UK's counter-terrorism strategy, CONTEST, and the challenges in its evaluation
(2016)
The UK’s Counter-Terrorism strategy, known as CONTEST, is recognized as one of the most successful soft-focus strategies in the world, with an intended emphasis on community support and what have become known as ‘Prevent’ (or counter-extremism) measures. In all, there are four limbs to CONTEST: PREVENT, PROTECT, PURSUE and PREPARE. While there is much crossover between these areas, for example policing activities take place in all four limbs, each one has a specific focus with its own intrinsic goals. This article intends to provide an overview of CONTEST, and to explore the challenges of evaluating counter-terrorism strategies in general. In doing so, I intend to show that while robust and independent evaluation of CONTEST has not been undertaken from a quantitative approach, some level of evaluation has taken place and can be taken into consideration when moving forward with future analysis of the strategy...
Report-no: UFTP-492/1999 Journal-ref: Phys.Rev. C61 (2000) 024909 We investigate flow in semi-peripheral nuclear collisions at AGS and SPS energies within macroscopic as well as microscopic transport models. The hot and dense zone assumes the shape of an ellipsoid which is tilted by an angle Theta with respect to the beam axis. If matter is close to the softest point of the equation of state, this ellipsoid expands predominantly orthogonal to the direction given by Theta. This antiflow component is responsible for the previously predicted reduction of the directed transverse momentum around the softest point of the equation of state.
French far right activism experienced tremendous changes in recent years. Besides traditional far right party politics, new patterns of street-based mobilization attract especially action-oriented youths. This trend is epitomized by the growing popularity of the Bloc Identitaire (official name; shortened to “Identitaires”). Its ideology rests on the idea that there exists a struggle between different political families in order to become the legitimate representative of the people, and that the extreme right is winning this struggle. Behind the scenes, the recurring idea of the Bloc Identitaires is to occupy a cultural and “meta-political” territory that was once the monopoly of the left. Their aim is that they are gradually associated with the only possible alternative to change the world. They try to frame a maximum of popular needs and present themselves as substitutes for when the economy and the state will be bankrupt. So you can eat the food of the Identitaires, drink their beer (the “Desouchière”), buy their clothes, listen to their music or read their books and thus participate in financing the movement...
How do coalition governments affect the risk of civil war onset in ethnically divided societies? Existing research argues that power-sharing coalitions decrease the risk of civil war because they redress grievances. Building on a formal model of coalition formation, we predict that ethnic elites are most likely to form oversized rather than minimum-winning coalitions in anticipation of future challenges to the regime. Put differently, we expect most power-sharing to occur where the risk of regime-threatening civil war is highest...
"Since the events of the eighteenth century, in particular the French and American Revolutions, the concept of revolution has become one of the most important, and most widely used, concepts of modern political and philosophical thought. The revolutions of the eighteenth century are, however, also marked by a temporal logic that questions their radical departure from the past, both intellectually and practically. Indeed, the concept of revolution is often coupled with a renewed interest in ideals of human self-conception, moral beauty and education that are seen as having emerged in the classical antiquity of Greece and Rome. On both sides of the Atlantic, references to classical antiquity support contemporary achievements, on the one hand, and are used to question the existing state of political and intellectual affairs, on the other."
We develop a dynamic network model with heterogenous banks which undertake optimizing portfolio decisions subject to liquidity and capital constraints and trade in the interbank market whose equilibrium is governed by a tatonnement process. Due to the micro-funded structure of the decisional process as well as the iterative dynamic adjustment taking place in the market, the links in the network structures are endogenous and evolve dynamically. We use the model to assess the diffusion of systemic risk (measured as default probability), the contribution of each bank to it as well as the evolution of the network in response to financial shocks and across different prudential policy regimes.
We develop a dynamic network model with heterogenous banks which undertake optimizing portfolio decisions subject to liquidity and capital constraints and trade in the interbank market whose equilibrium is governed by a tatonnement process. Due to the micro-funded structure of the decisional process as well as the iterative dynamic adjustment taking place in the market, the links in the network structures are endogenous and evolve dynamically. We use the model to assess the diffusion of systemic risk, the contribution of each bank to it as well as the evolution of the network in response to financial shocks and across different prudential policy regimes.
Is wider access to stockholding opportunities related to reduced wealth inequality, given that it creates challenges for small and less sophisticated investors? Counterfactual analysis is used to study the influence of changes in the US stockholder pool and economic environment, on the distribution of stock and net household wealth during a period of dramatic increase in stock market participation. We uncover substantial shifts in stockholder pool composition, favoring smaller holdings during the 1990s upswing but larger holdings around the burst of the Internet bubble. We find no evidence that widening access to stocks was associated with reduced net wealth inequality.
In hindsight, the debate about presupposition following Frege’s discovery that the referential function of names and definite descriptions depended on the fulfillment of an existence and a uniqueness condition was curiously limited for a very long time. On the one hand, it was only in the 1960s that linguists began to take an interest and showed that presupposition was an allpervasive phenomenon far beyond this philosophers’ pet definite descriptions. And on the other hand, and this is our real concern, it is now only too obvious that the uniqueness condition is too restrictive to be applicable to the general case. An utterance of “The cat is on the mat” should not imply that there is only one cat and one mat in the whole world. The obvious move is to limit the uniqueness condition to some notion of utterance context.
The distribution of linguistic structures in the world is the joint product of universal principles, inheritance from ancestor languages, language contact, social structures, and random fluctuation. This paper proposes a method for evaluating the relative significance of each factor — and in particular, of universal principles — via regression modeling: statistical evidence for universal principles is found if the odds for families to have skewed responses (e.g. all or most members have postnominal relative clauses) as opposed to having an opposite response skewing or no skewing at all, is significantly higher for some condition (e.g. VO order) than for another condition, independently of other factors.
It is often assumed that the goal of typology is to define the notion ‘possible human language’. This view, which I call the Universalist Typology view is shared, for example, by virtually all contributors to Bynon & Shibatani’s 1995 volume Approaches to Language Typology, and by Moravscik in her review of this volume in Linguistic Typology 1 (p.105). In the following I claim that this assumption is fundamentally mistaken. To clarify the theoretical status of what is meant by ‘possible human language’, I argue here for a distinction between typological theory (theoretical typology) and grammatical theory (theoretical syntax and theoretical morphology) as distinct subdisciplines of linguistics.
Languages vary in whether or not primary grammatical relations (PGRs) are sensitive to information from clause-level case or phrase structures. This variation correlates with a difference between verb agreement systems based on feature unification and systems based on feature composition. The choice between different PGR and agreement principles is found to be highly stable genetically and to characterize Indo-European as systematically different from Sino-Tibetan. Although the choice is partially similar to the Configurationality Parameter, it is shown that Indo-European languages of South Asia are nonconfigurational due to areal pressure but follow their European relatives in PGR and agreement principles.
Ever since Wilhelm von Humboldt’s (1836) pioneering study of Nahuatl, linguists have recurrently recognized that languages differ fundamentally in the syntactic weight they attribute to noun-phrases as the arguments of a verb. Currently, the most prominent attempts to turn this intuition into a precise hypothesis revolve around the notion of ‘configurationality’.
In Belhare (Sino-Tibetan, Nepal), consonant prothesis at morpheme boundaries and deletion of stem "augments" is found if either metrical or morphological parsing would violate the bimoraic trochee pattern that underlies the stress system of the language. This finding corroborates Dresher & Lahiri’s (1991) "Principle of Metrical Coherence" and provides new evidence for the cross-linguistic applicability of Crowhurst’s (1994) "Tautomorphemic Foot" constraint. The data also support a view of the Prosodic Hierarchy as weakly layered, allowing consonants to be directly dominated by the foot or word node if they are prothetic and do not therefore need feature licensing within the syllable canon.
This is the first article in our series on refugees.Attempts to address the current crisis often seek to make distinctions between ‘refugees’ and ‘migrants’ and between refugees / migrants and citizens. But, I suggest, these distinctions are part of the problem. Part of the solution is to rethink our histories of ‘national states’ – and the rights and claims they enable – through a ‘connected sociologies’ approach that acknowledges the shared histories that bring states and colonies together....
The dualism of movements and institutions. A structurational approach towards the two concepts
(2016)
In studies of social mobilization, the distinction between institutions and organizations is often as blurry as the instant of time from which on we can actually speak of a proper movement. Using the idea of a `duality of structure’ as a starting point, this article suggests a way of fixing the boundaries: a brief analysis of the South African Landless People’s Movement demonstrates the merit of conceiving of movements as aggregate actors with shared common objectives and common norms, which institutionalize particular modes of cooperation by purposefully drawing on existing institutions in order to shape functioning internal structures.
Persons traveling to participate in foreign conflicts by no means constitute a new phenomenon that is intrinsically tied to the ‘Islamic State’ (‘IS’). However, law enforcement agencies all over the world increasingly focus on foreign fighters travelling to Syria and Iraq due to a considerable rise in their number as well as the perceived threat they pose upon their return. Currently, around 650 German residents and citizens have travelled to the region to support jihadist groups such as the ‘IS’.
On October the 2nd the Colombian people rejected the peace agreement between the government and the FARC in a referendum with a very thin majority of 0.4%. With this unexpected rejection, the referendum was in some ways similar to the Brexit referendum, for the results of which David Cameron was as little prepared as Juan Manuel Santos for his rejection; there was obviously no Plan B. In the last weeks, the government undertook ten changes to the agreement, but it will not go through a referendum again. Santos, as he said, has learned his lesson from the rejection and will seek to have the amended peace agreement approved in Congress. This will likely lead to the implementation of the peace agreement and the furtherance of its goals, such as a DDR process, land reforms, a transitional justice process and reparations for victims, just to mention a few. But this progress in peace will be seen as being at odds with popular opinion. Many of the “no” voters are still not satisfied with the adjustments made by the government and the FARC, and neither are the sectors of the opposition mainly responsible for the rejection. Nevertheless, the government and the FARC are progressing with the implementation, and peace talks with the second-largest – and now the last standing – guerrilla group, the ELN, are scheduled to start in 2017. The prospects for 2018 and onwards, when the presidency election will be held, are more questionable.