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1.
Alexandros Kapsomenakis Panagiotis G. Simos Georgios Konstantakopoulos Dimitrios S. Kasselimis 《Journal of gambling studies / co-sponsored by the National Council on Problem Gambling and Institute for the Study of Gambling and Commercial Gaming》2018,34(4):1327-1340
Pathological gambling is characterized by a persisting maladaptive and recurrent behavior with severe social and psychological consequences. There is evidence of strong comorbidity with psychiatric manifestations as well as cognitive mainly involving executive functions. This study aimed to investigate impairment in executive functions and working memory, and personality traits in a sample of Greek gamblers. Twenty-four men involved in various gambling activities were recruited from ecological settings as probable pathological gamblers. They were assessed with a comprehensive neuropsychological battery involving several executive tasks, the Zuckerman–Kuhlman Personality Questionnaire, the Hospital Anxiety Depression Scale, and the Difficulties in Emotion Regulation Scale. An age- and education-level matched group of 21 men without history of habitual gambling served as controls. As a group, gamblers displayed significantly lower scores on indices of inhibition, decision making and self-reported emotional awareness, and scored higher on impulsivity/sensation seeking personality traits. Notably, gamblers scored similarly or significantly higher on measures of verbal and visuospatial working memory, cognitive flexibility, processing speed, verbal fluency, and sustained attention. Overall, we argue that gamblers do present with specific cognitive deficits, but there is no evidence for a generalized executive impairment, and further stress the importance of investigating cognitive, personality, and psychiatric aspects of gambling on the basis of an ecologically valid sampling. 相似文献
2.
The use of GARCH models in VaR estimation 总被引:6,自引:0,他引:6
Timotheos Angelidis Alexandros Benos Stavros Degiannakis 《Statistical Methodology》2004,1(1-2):105-128
We evaluate the performance of an extensive family of ARCH models in modeling the daily Value-at-Risk (VaR) of perfectly diversified portfolios in five stock indices, using a number of distributional assumptions and sample sizes. We find, first, that leptokurtic distributions are able to produce better one-step-ahead VaR forecasts; second, the choice of sample size is important for the accuracy of the forecast, whereas the specification of the conditional mean is indifferent. Finally, the ARCH structure producing the most accurate forecasts is different for every portfolio and specific to each equity index. 相似文献
3.
The main purpose of this work is to decompose the predictive performance of the moving average (MA) trading rule and find out the portion that could be attributed to the possible exploitation of linear and non-linear dependencies in stock returns. Data from the General Index of the Athens Stock Exchange, from the Standard and Poor-500 Index of the New York Stock Exchange and from the Austrian Traded Index of the Vienna Stock Exchange are filtered by linear filters so as the resulting simulated ‘returns’ exhibit no serial correlation. Applying MA trading rules to both the original and the simulated indices and using a new statistical testing procedure that takes into account the sensitivity of the performance of the trading rule as a function of the length of the MA it is found that the predictive performance of the trading rule is clearly weakened when applied to the simulated indices indicating that a substantial part of the rule's predictive performance is due to the exploitation of linear dependencies in stock returns. This weakening is uneven; in general the shorter the MA length the more pronounced the attenuation. 相似文献
4.
Statistics and Computing - In variational inference (VI), coordinate-ascent and gradient-based approaches are two major types of algorithms for approximating difficult-to-compute probability... 相似文献
5.
During the 90s, PASOK, in common with the other European social democratic parties has advocated Third Way revisionism and has placed the‘modernization’of the Greek society high on its political agenda. By focusing on a series of conflictual incidents between the teacher unions and the Greek government, this paper exemplifies the repercussion of this process on teachers‐state relations. Building upon the dialecties of path shaping and path dependency, we suggest that the particular development of the modernization project and the reactions it has triggered are to be attributed to the historically determined, nationally specific, contingently activated institutional legacies and structures that, on the one hand, stand in the way of the incorporation of Greece to the EMU/ESM and, on the other, are employed by the unions to defend industrial and social citizenship. 相似文献
6.
Rea Prouska Margarita Nyfoudi Alexandros Psychogios Leslie T. Szamosi Adrian Wilkinson 《英国管理杂志》2023,34(1):91-110
Solidarity behaviour (SB) among employees is important in building a sense of community in organizations, particularly within a crisis context where adverse working conditions prevail. However, we have limited knowledge concerning how SB develops. Using the lens of social exchange theory, this study examines how top-down communication and employee voice relate to horizontal (employee to emplCoyee) SB. We conducted two comprehensive studies during the Greek economic crisis and found that the relationship between top-down employee communication and horizontal SB is mediated by employee voice. The paper extends our existing knowledge in the fields of management and human resource management by advancing our understanding of horizontal SB, highlighting the role of top-down employee communication as an effective human resource practice and delineating the role of employee voice in fostering workplace camaraderie in small and medium-sized enterprises under crisis. 相似文献
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8.
Alexandros Kioupkiolis 《Social movement studies》2018,17(1):99-112
‘Post-hegemony’ is a critical notion introduced by theorists who take issue with the modern politics of hierarchical organization, representation, unification, the state and ideology: the politics of ‘hegemony’ according to A. Gramsci and E. Laclau. Post-hegemonic thinkers tend to celebrate, by contrast, contemporary social movements which appear to be horizontal, leaderless, participatory, diverse, networked and opposed to the state, global capitalism and ideological closures. Critical responses to the ‘post-hegemonic’ thesis object that contemporary democratic resistances do not attain, in effect, a full rupture with hegemony or they should not attain it. The paper offers, first, an illuminating, up-to-date map of the different positions in the debate over post-hegemony. It seeks to demonstrate, then, that diverse figures of contemporary activism are indeed post-hegemonic not as this has been understood in most post-hegemonic accounts till now, but in the sense of the ‘post-’ which implies an impure, ongoing development: a time and a space in-between. The second half of the paper is devoted, thus, to recasting and reformulating the conception of post-hegemony, tracing it out in the values, the practices and the logics which inform recent democratic movements, as these craft new modes of unification, leadership and representation beyond the hegemonic mould. 相似文献
9.
Alexandros Psychogios Margarita Nyfoudi Nicholas Theodorakopoulos Leslie T. Szamosi Rea Prouska 《英国管理杂志》2019,30(3):519-537
What is the relationship between adverse working conditions and employees’ organizational citizenship behaviour (OCB) in small and medium‐sized enterprises (SMEs) operating under a severe economic crisis? To address this question, a survey of 312 front‐line workers was undertaken in 62 Greek SMEs ? an instrumental setting where the current deterioration of working conditions is acute. Our contribution is twofold. First, we develop and test a scale for measuring adverse working conditions. Second, we decipher the extent to which such conditions relate to organizational and individual aspects of OCB, considering job satisfaction's mediating role. Through this research we extend the OCB literature within the context of SMEs operating under severe economic crisis and highlight the implications for managing human resources in SMEs, a sector conspicuous for its socio‐economic significance and its vulnerability during economic downturns. 相似文献
10.
Alexandros Karagrigoriou 《统计学通讯:理论与方法》2013,42(4):911-930
Motivated by Shibata’s (1980) asymptotic efficiency results this paper dis-cusses the asymptotic efficiency of the order selected by a selection procedure for an infinite order autoregressive process with nonzero mean and unob servable errors that constitute a sequence of independent Gaussian random variables with mean zero and variance σ2 The asymptotic efficiency is established for AIC–type selection criteria such as AIC’, FPE, and Sn(k). In addition, some asymptotic results about the estimators of the parameters of the process and the error–sequence are presented. 相似文献