Refine
Year of publication
Document Type
- Article (30570)
- Part of Periodical (11906)
- Book (8260)
- Doctoral Thesis (5708)
- Part of a Book (3721)
- Working Paper (3386)
- Review (2878)
- Contribution to a Periodical (2369)
- Preprint (2077)
- Report (1544)
Language
- German (42456)
- English (29259)
- French (1067)
- Portuguese (723)
- Multiple languages (309)
- Croatian (302)
- Spanish (301)
- Italian (195)
- mis (174)
- Turkish (148)
Is part of the Bibliography
- no (75259) (remove)
Keywords
- Deutsch (1038)
- Literatur (809)
- taxonomy (760)
- Deutschland (543)
- Rezension (491)
- new species (449)
- Frankfurt <Main> / Universität (341)
- Rezeption (325)
- Geschichte (292)
- Linguistik (268)
Institute
- Medizin (7694)
- Präsidium (5190)
- Physik (4463)
- Wirtschaftswissenschaften (2698)
- Extern (2661)
- Gesellschaftswissenschaften (2373)
- Biowissenschaften (2184)
- Biochemie und Chemie (1974)
- Frankfurt Institute for Advanced Studies (FIAS) (1687)
- Center for Financial Studies (CFS) (1630)
This paper sets the background for the Special Issue of the Journal of Empirical Finance on the European Sovereign Debt Crisis. It identifies the channel through which risks in the financial industry leaked into the public sector. It discusses the role of the bank rescues in igniting the sovereign debt crisis and reviews approaches to detect early warning signals to anticipate the buildup of crises. It concludes with a discussion of potential implications of sovereign distress for financial markets.
This paper investigates whether the overpricing of out-of-the money single stock calls can be explained by Tversky and Kahneman’s (1992) cumulative prospect theory (CPT). We argue that these options are overpriced because investors overweight small probability events and overpay for such positively skewed securities, i.e., characteristics of lottery tickets. We match a set of subjective density functions derived from risk-neutral densities, including CPT with the empirical probability distribution of U.S. equity returns. We find that overweighting of small probabilities embedded in CPT explains on average the richness of out-of-the money single stock calls better than other utility functions. The degree that agents overweight small probability events is, however, strongly timevarying and has a horizon effect, which implies that it is less pronounced in options of longer maturity. We also find that time-variation in overweighting of small probabilities is strongly explained by market sentiment, as in Baker and Wurgler (2006).
Low probability events are overweighted in the pricing of out-of the-money index puts and single stock calls. We find that this behavioral bias is strongly time-varying, linked to equity market sentiment, and higher moments of the risk-neutral density. An implied volatility (IV) sentiment measure that is jointly derived from index and single stock options explains investors' overweight of tail events the best. Our findings also suggest that IV-sentiment predicts equity markets reversals better than overweight of small probabilities itself. When employed in a trading strategy, IV-sentiment delivers economically significant results, which are more consistent than the ones produced by the market sentiment factor. The joint use of information from the single stock and index option markets seems to explain the forecasting power of IV-sentiment. Out-of-sample tests on reversal prediction show that our IV-sentiment measure adds value over and above traditional factors in the equity risk premium literature, especially as an equity-buying signal. This reversals prediction seems to improve time-series and cross-sectional momentum strategies.
Objective: The aim of this study was to assess the potential risk of gadobutrol-enhanced magnetic resonance imaging (MRI) in patients with moderate to severe renal impairment for the development of nephrogenic systemic fibrosis (NSF).
Materials and Methods: We performed a prospective, international, multicenter, open-label study in 55 centers. Patients with moderate to severe renal impairment scheduled for any gadobutrol-enhanced MRI were included. All patients received a single intravenous bolus injection of gadobutrol at a dose of 0.1 mmol/kg body weight. The primary target variable was the number of patients who develop NSF within a 2-year follow-up period.
Results: A total of 908 patients were enrolled, including 586 with moderate and 284 with severe renal impairment who are at highest risk for developing NSF. The mean time since renal disease diagnosis was 1.83 and 5.49 years in the moderate and severe renal impairment cohort, respectively. Overall, 184 patients (20.3%) underwent further contrast-enhanced MRI with other gadolinium-based contrast agents within the 2-year follow-up. No patient developed symptoms conclusive of NSF.
Conclusions: No safety concerns with gadobutrol in patients with moderate to severe renal impairment were identified. There were no NSF cases.
BACKGROUND: The analysis of microarray time series promises a deeper insight into the dynamics of the cellular response following stimulation. A common observation in this type of data is that some genes respond with quick, transient dynamics, while other genes change their expression slowly over time. The existing methods for detecting significant expression dynamics often fail when the expression dynamics show a large heterogeneity. Moreover, these methods often cannot cope with irregular and sparse measurements.
RESULTS: The method proposed here is specifically designed for the analysis of perturbation responses. It combines different scores to capture fast and transient dynamics as well as slow expression changes, and performs well in the presence of low replicate numbers and irregular sampling times. The results are given in the form of tables including links to figures showing the expression dynamics of the respective transcript. These allow to quickly recognise the relevance of detection, to identify possible false positives and to discriminate early and late changes in gene expression. An extension of the method allows the analysis of the expression dynamics of functional groups of genes, providing a quick overview of the cellular response. The performance of this package was tested on microarray data derived from lung cancer cells stimulated with epidermal growth factor (EGF).
CONCLUSION: Here we describe a new, efficient method for the analysis of sparse and heterogeneous time course data with high detection sensitivity and transparency. It is implemented as R package TTCA (transcript time course analysis) and can be installed from the Comprehensive R Archive Network, CRAN. The source code is provided with the Additional file 1.
Donald Trump’s foreign policy agenda has been characterized as unpredictable, unprecedented and – after a telling neologism of the president himself – unpresidented. In this blog post I will argue that the constituent parts of Trump’s foreign policy are all but new. What is new is their combination. Moreover, while Trump’s Jeffersonianism-Jacksonianism stands in stark contrast to the Wilsonianism-Hamiltonianism that Hillary Clinton embraced during her election campaign, it is only a partial departure from Barack Obama’s Jeffersonianism-Hamiltonianism.
Das Yin und Yang des Terrors
(2017)
Man stelle sich folgendes Szenario vor: Björn Höcke und Abū Bakr al-Baġdādī diskutieren bei Sandra Maischberger darüber, welche Konsequenzen Deutschland aus dem islamistischen Terrorismus ziehen sollte – und sie sind sich dabei einig.
Die Fiktion mag hanebüchen klingen. Nicht nur, weil der Möchtegern-Kalif des „Islamischen Staats“ (IS) unter keinen Umständen als Gast einer deutschen Talkshow in Erscheinung treten könnte – oder auch nur wollte. Sondern auch, weil der Möchtegern-Goebbels aus Thüringen sich stets als ritterlicher Gegner der Islamisten präsentiert, deren Denken und Handeln völlig unvereinbar sei mit dem Willen des hiesigen Volkes, den die Rechtspopulisten zu repräsentieren meinen. Gleicht man allerdings die (migrations-)politischen Willensbekundungen, die AFD und Co. als Antwort auf den islamistischen Terror bieten, ab mit den politischen Reaktionen, die sich der IS von Anschlägen in Europa erhofft, fällt es schwer, hier einen Widerspruch zu sehen. Vielmehr lässt ein solcher Abgleich die deutschen – und auch europäischen – Rechtspopulisten, für die Höcke hier stellvertretend steht, fast schon als heimliche Partner des IS erscheinen, deren Absichten sich bestens mit den Vorstellungen der IS-Strategen ergänzen.
Damit ist ein dialektisches Problem angesprochen, das dem Umgang mit dem Terrorismus stets inhärent ist. Immerhin gehört es zu den Binsenweisheiten der Konfliktforschung, dass terroristische Akteure Reaktionen provozieren wollen, die ihnen neue Handlungsmöglichkeiten eröffnen. Und dies wiederum verweist darauf, dass Politiker und Sicherheitsbehörden, aber auch die Medien dabei (ungewollt) zu Erfüllungsgehilfen werden können, wenn deren Reflexe dem terroristischen Kalkül entsprechen. Die Dynamik des Terrors speist sich eben nicht nur aus den Aktionen der Terroristen, sondern auch aus dem Verhalten ihrer Antagonisten und der Öffentlichkeit. Um jene Dynamik zu verstehen, reicht daher der Blick auf terroristische Strategien keineswegs aus. Vielmehr ist deren Effekt von den Reaktionen relationaler Akteure abhängig. Wer also dem Terrorismus das Wasser abgraben will, der muss – so paradox das klingt – auch Vorsicht gegenüber denen walten lassen, die Anstoß an ihm nehmen.
Diese Prämisse eröffnet eine kritische Perspektive auf Formen des Anti-Terrorismus. Denn demnach können Versuche, dem Terror die Stirn zu bieten, unbeabsichtigte (Neben-)Folgen mit sich bringen, welche die Dynamik des Terrors verstärken. Derartige backfire mechanisms sind es, die in diesem Beitrag problematisiert werden. Jedoch widmet er sich nicht der staatlichen Antiterrorpolitik, sondern erörtert, inwiefern das Zusammenspiel von Medien und Rechtspopulismus zur aktuellen Dynamik des islamistischen Terrorismus beiträgt. Diese Frage stellt sich vor dem Hintergrund, dass die jüngsten Anschläge in Europa eine virtuelle Form des Terrorismus darstellen, wo häufig Einzelpersonen im Namen des IS agieren, aber kaum bis gar nicht im Kontakt mit der Organisation standen. Es scheint daher die Vermutung nicht abwegig, dass co-konstitutive Faktoren – wie die Berichterstattung über den Terror und anti-muslimische Diskurse – eine nicht unbedeutende Rolle bei deren Radikalisierung und Aktivierung spielen.
In this meeting report, particularly addressing the topic of protection of the cardiovascular system from ischemia/reperfusion injury, highlights are presented that relate to conditioning strategies of the heart with respect to molecular mechanisms and outcome in patients’ cohorts, the influence of co-morbidities and medications, as well as the contribution of innate immune reactions in cardioprotection. Moreover, developmental or systems biology approaches bear great potential in systematically uncovering unexpected components involved in ischemia–reperfusion injury or heart regeneration. Based on the characterization of particular platelet integrins, mitochondrial redox-linked proteins, or lipid-diol compounds in cardiovascular diseases, their targeting by newly developed theranostics and technologies opens new avenues for diagnosis and therapy of myocardial infarction to improve the patients’ outcome.