1,720,999 research outputs found
Dynamic large financial networks via conditional expected shortfalls
Get PDFIn this article, we first generalize the Conditional Auto-Regressive Expected Shortfall (CARES) model by introducing the loss exceedances of all (other) listed companies in the Expected Shortfall related to each firm, thus proposing the CARES-X model (where the ‘X’, as usual, stands for eXtended in the case of large-dimensional problems). Second, we construct a regularized network of US financial companies by introducing the Least Absolute Shrinkage and Selection Operator in the estimation step. Third, we also propose a calibration approach for uncovering the relevant edges between the network nodes, finding that the estimated network structure dynamically evolves through different market risk regimes. We ultimately show that knowledge of the extreme risk network links provides useful information, since the intensity of these links has strong implications on portfolio risk. Indeed, it allows us to design effective risk management mitigation allocation strategies
A meta-measure of performance related to both investors and investments characteristics
No full textWe introduce hereafter a new flexible meta-measurement of portfolio performance, called the Generalized Utility-based N-moment measure, relying both on a characterization of the whole return distribution and on the set of preferences of the investor, which is adapted to analyze the performance of hedge funds. It could also serve as the basis of a Fraudulent Behavior Index aiming to detect fraudulent funds
Systemic risk and severe economic downturns: A targeted and sparse analysis
Get PDFRecent studies indicate that systemic risk has predictive power over severe economic downturns. We propose a novel methodology that employs sparsity and targeting approaches to optimally select and combine systemic risk measures to forecast the tail of a given economic variable. Out-of-sample analysis shows that the optimal combination of systemic risk metrics may vary over time, forecasting horizons and economic proxies. Moreover, a few systemic risk measures contain all the important information for capturing the relation between systemic risk and real economy; therefore, a fixed and static combination approach may not be optimal, and the flexible parsimonious extension we introduce leads to improvement in forecasting performance
Omega Compatibility: A Meta-analysis
No full textThe Omega performance measure introduced by Keating and Shadwick (An introduction to Omega. AIMA Newsletter, 2002a; J Perform Meas 6(3):59-84, 2002b) is widely used in asset allocation and performance measurement. We contribute to the debates around this measure by focusing on its relation and compatibility with Second-order Stochastic Dominance, introducing two conditions of compatibility: the Non-Strict Dominance Compatibility and the Strict Dominance Compatibility conditions. We show that Omega is compatible with the First-order Stochastic Dominance criterion when using the Non-Strict Dominance Compatibility condition (as already shown), but also in the sense of the Strict Dominance Compatibility condition. We also prove again that Omega is compatible with Second-order Stochastic Dominance when using the Non-Strict Dominance Compatibility condition, but only under some conditions on the threshold used in the computation of the Omega measure, as usual. However, we finally also show that Omega is not compatible (i.e. incompatible) with Second-order Stochastic Dominance criterion when using the Strict Dominance Compatibility condition. We further provide a critical meta-analysis that separates good from approximate statements when comparing the views and results provided in many articles on the topic and point out that the use of Omega in asset selection and optimal asset allocation may entail real computational economics issues and may lead to unreasonable financial decisions. Finally, trying to avoid further disputes, ill-posed optimization procedures, and ultimately incorrect economic decisions in computational financial applications, we recall the main potential drawbacks of Omega that, in our opinion, mainly lies in its incompatibility with the Second-order Stochastic Dominance criterion under the Strict Dominance Compatibility condition
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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