715 resultados para Idiosyncratic skewness


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Research shows that intention for intra-family succession is an important determinant of family firm behavior. To provide a systematic analysis of the antecedents of such intention, we use the theory of planned behavior to model the incumbent leader’s attitude toward intra-family succession because that particular attitude is idiosyncratic to family firms. Empirical tests using a sample of 271 Italian incumbent leaders of family firms show that, as predicted by planned behavior theory, attitude and self-efficacy are significant predictors of intention. They show further that attitude is affected by the number of children, emotional attachment, and need for control.

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Thesis (Master's)--University of Washington, 2016-06

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Thesis (Ph.D.)--University of Washington, 2016-06

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The metabolic conjugation of exogenous and endogenous carboxylic acid substrates with endogenous glucuronic acid, mediated by the uridine diphosphoglucuronosyl transferase (UGT) superfamily of enzymes, leads to the formation of acyl glucuronide metabolites. Since the late 1970s, acyl glucuronides have been increasingly identified as reactive electrophilic metabolites, capable of undergoing three reactions: intramolecular rearrangement, hydrolysis, and intermolecular reactions with proteins leading to covalent drug-protein adducts. This essential dogma has been accepted for over a decade. The key question proposed by researchers, and now the pharmaceutical industry, is: does or can the covalent modification of endogenous proteins, mediated by reactive acyl glucuronide metabolites, lead to adverse drug reactions, perhaps idiosyncratic in nature? This review evaluates the evidence for acyl glucuronide-derived perturbation of homeostasis, particularly that which might result from the covalent modification of endogenous proteins and other macromolecules. Because of the availability of acyl glucuronides for test tube/in vitro experiments, there is now a substantial literature documenting their rearrangement, hydrolysis and covalent modification of proteins in vitro. It is certain from in vitro experiments that serum albumin, dipeptidyl peptidase IV, tubulin and UGTs are covalently modified by acyl glucuronides. However, these in vitro experiments have been specifically designed to amplify any interference with a biological process in order to find biological effects. The in vivo situation is not at all clear. Certainly it must be concluded that all humans taking carboxylate drugs that form reactive acyl glucuronides will form covalent drug-protein adducts, and it must also be concluded that this in itself is normally benign. However, there is enough in vivo evidence implicating acyl glucuronides, which, when backed up by in vivo circumstantial and documented in vitro evidence, supports the view that reactive acyl glucuronides may initiate toxicity/immune responses. In summary, though acyl glucuronide-derived covalent modification of endogenous macromolecules is well-defined, the work ahead needs to provide detailed links between such modification and its possible biological consequences. (C) 2003 Elsevier Science Ireland Ltd. All rights reserved.

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A test of the ability of a probabilistic neural network to classify deposits into types on the basis of deposit tonnage and average Cu, Mo, Ag, Au, Zn, and Pb grades is conducted. The purpose is to examine whether this type of system might serve as a basis for integrating geoscience information available in large mineral databases to classify sites by deposit type. Benefits of proper classification of many sites in large regions are relatively rapid identification of terranes permissive for deposit types and recognition of specific sites perhaps worthy of exploring further. Total tonnages and average grades of 1,137 well-explored deposits identified in published grade and tonnage models representing 13 deposit types were used to train and test the network. Tonnages were transformed by logarithms and grades by square roots to reduce effects of skewness. All values were scaled by subtracting the variable's mean and dividing by its standard deviation. Half of the deposits were selected randomly to be used in training the probabilistic neural network and the other half were used for independent testing. Tests were performed with a probabilistic neural network employing a Gaussian kernel and separate sigma weights for each class (type) and each variable (grade or tonnage). Deposit types were selected to challenge the neural network. For many types, tonnages or average grades are significantly different from other types, but individual deposits may plot in the grade and tonnage space of more than one type. Porphyry Cu, porphyry Cu-Au, and porphyry Cu-Mo types have similar tonnages and relatively small differences in grades. Redbed Cu deposits typically have tonnages that could be confused with porphyry Cu deposits, also contain Cu and, in some situations, Ag. Cyprus and kuroko massive sulfide types have about the same tonnages. Cu, Zn, Ag, and Au grades. Polymetallic vein, sedimentary exhalative Zn-Pb, and Zn-Pb skarn types contain many of the same metals. Sediment-hosted Au, Comstock Au-Ag, and low-sulfide Au-quartz vein types are principally Au deposits with differing amounts of Ag. Given the intent to test the neural network under the most difficult conditions, an overall 75% agreement between the experts and the neural network is considered excellent. Among the largestclassification errors are skarn Zn-Pb and Cyprus massive sulfide deposits classed by the neuralnetwork as kuroko massive sulfides—24 and 63% error respectively. Other large errors are the classification of 92% of porphyry Cu-Mo as porphyry Cu deposits. Most of the larger classification errors involve 25 or fewer training deposits, suggesting that some errors might be the result of small sample size. About 91% of the gold deposit types were classed properly and 98% of porphyry Cu deposits were classes as some type of porphyry Cu deposit. An experienced economic geologist would not make many of the classification errors that were made by the neural network because the geologic settings of deposits would be used to reduce errors. In a separate test, the probabilistic neural network correctly classed 93% of 336 deposits in eight deposit types when trained with presence or absence of 58 minerals and six generalized rock types. The overall success rate of the probabilistic neural network when trained on tonnage and average grades would probably be more than 90% with additional information on the presence of a few rock types.

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In this paper we investigate a Bayesian procedure for the estimation of a flexible generalised distribution, notably the MacGillivray adaptation of the g-and-κ distribution. This distribution, described through its inverse cdf or quantile function, generalises the standard normal through extra parameters which together describe skewness and kurtosis. The standard quantile-based methods for estimating the parameters of generalised distributions are often arbitrary and do not rely on computation of the likelihood. MCMC, however, provides a simulation-based alternative for obtaining the maximum likelihood estimates of parameters of these distributions or for deriving posterior estimates of the parameters through a Bayesian framework. In this paper we adopt the latter approach, The proposed methodology is illustrated through an application in which the parameter of interest is slightly skewed.

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Birds show striking interspecific variation in their use of carotenoid-based coloration. Theory predicts that the use of carotenoids for coloration is closely associated with the availability of carotenoids in the diet but, although this prediction has been supported in single-species studies and those using small numbers of closely related species, there have been no broad-scale quantitative tests of the link between carotenoid coloration and diet. Here we test for such a link using modern comparative methods, a database on 140 families of birds and two alternative avian phylogenies. We show that carotenoid pigmentation is more common in the bare parts (legs, bill and skin) than in plumage, and that yellow coloration is more common than red. We also show that there is no simple, general association between the availability of carotenoids in the diet and the overall use of carotenoid-based coloration. However, when we look at plumage coloration separately from bare part coloration, we find there is a robust and significant association between diet and plumage coloration, but not between diet and bare part coloration. Similarly, when we look at yellow and red plumage colours separately, we find that the association between diet and coloration is typically stronger for red coloration than it is for yellow coloration. Finally, when we build multivariate models to explain variation in each type of carotenoid-based coloration we find that a variety of life history and ecological factors are associated with different aspects of coloration, with dietary carotenoids only being a consistent significant factor in the case of variation in plumage. All of these results remain qualitatively unchanged irrespective of the phylogeny used in the analyses, although in some cases the precise life history and ecological variables included in the multivariate models do vary. Taken together, these results indicate that the predicted link between carotenoid coloration and diet is idiosyncratic rather than general, being strongest with respect to plumage colours and weakest for bare part coloration. We therefore suggest that, although the carotenoid-based bird plumage may a good model for diet-mediated signalling, the use of carotenoids in bare part pigmentation may have a very different functional basis and may be more strongly influenced by genetic and physiological mechanisms, which currently remain relatively understudied.

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A 34-year-old female patient with a three year history of generalized granuloma annulare was treated systemically with dapsone (DADPS). Six weeks after the onset of treatment, the patient developed an extensive tonsillitis of the base of the tongue with fever and malaise. Routine laboratory work showed a leukocytopenia with agranulocytosis. Further investigation revealed a marked decrease of the enzyme activity of N-acetyltransferase 2, which plays an important role in dapsone metabolism. Treatment included the cessation of dapsone, antibiotic coverage, and G-CSF leading to the rapid improvement of symptoms and normalization of leukocyte counts. Dapsone-induced angina agranulocytotica is a rare event and is interpreted as an idiosyncratic reaction. Depending on genetic polymorphisms of various enzymes, dapsone can be metabolized to immunologically or toxicologically relevant intermediates. Because of the risk of severe hematologic reactions, dapsone should only be employed for solid indications and with appropriate monitoring.

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The recent deregulation in electricity markets worldwide has heightened the importance of risk management in energy markets. Assessing Value-at-Risk (VaR) in electricity markets is arguably more difficult than in traditional financial markets because the distinctive features of the former result in a highly unusual distribution of returns-electricity returns are highly volatile, display seasonalities in both their mean and volatility, exhibit leverage effects and clustering in volatility, and feature extreme levels of skewness and kurtosis. With electricity applications in mind, this paper proposes a model that accommodates autoregression and weekly seasonals in both the conditional mean and conditional volatility of returns, as well as leverage effects via an EGARCH specification. In addition, extreme value theory (EVT) is adopted to explicitly model the tails of the return distribution. Compared to a number of other parametric models and simple historical simulation based approaches, the proposed EVT-based model performs well in forecasting out-of-sample VaR. In addition, statistical tests show that the proposed model provides appropriate interval coverage in both unconditional and, more importantly, conditional contexts. Overall, the results are encouraging in suggesting that the proposed EVT-based model is a useful technique in forecasting VaR in electricity markets. (c) 2005 International Institute of Forecasters. Published by Elsevier B.V. All rights reserved.

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This paper explores the extent to which it is possible to address issues pertaining to developing countries with significant socio-cultural and political interventions. Examples from the Sri Lankan tea plantations are used to illustrate the necessity to understand the context from actors’ perspectives using rigorous case study research, before making prescriptive recommendations. Current problems faced by the Sri Lankan tea industry are identified as not merely micro-institutional or managerial. We argue that their roots lie in reproduction of social struggles at the level of production. We propose a research agenda, in the doctrine of critical theory, for exploring the formation and implementation of business strategies in developing countries, using the tea plantation sector as a case. Our primary attempt here is to conceptualize strategic management in the context of political economy and to identify central issues to be addressed. Accordingly, we argue that researching historical dynamics of strategic management facilitates understanding and interpreting the articulation of modes of production in a given social formation. We further argue that a highly context specific research agenda is required to fully comprehend idiosyncratic characteristics of Sri Lankan strategy structures and organizational forms. Then, it is proposed that explaining the role of social formation in shaping and reshaping strategy relations should be at the centre of the research due to the social significance attached to ‘strategy’. Finally, methodological and epistemological necessities arising from the nature of strategy relationships are discussed.

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Many organisations are encouraging their staff to integrate work and non-work, but a qualitative study of young professionals found that many crave greater segregation rather than more integration. Most wished to build boundaries to separate the two and simplify a complex world. Where working practices render traditional boundaries of time and space ineffective, this population seems to create new idiosyncratic boundaries to segregate work from non-work. These idiosyncratic boundaries depended on age, culture and life-stage though for most of this population there was no appreciable gender difference in attitudes to segregating work and non-work. Gender differences only became noticeable for parents. A matrix defining the dimensions to these boundaries is proposed that may advance understanding of how individuals separate their work and personal lives. In turn, this may facilitate the development of policies and practices to integrate work and non-work that meet individual as well as organisational needs.

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The aim of this study is to examine the relationship between momentum profitability and the stock market trading mechanism and is motivated by recent changes to the trading systems that have taken place on the London Stock Exchange. Since 1975 the London stock market has employed three different trading systems: a floor based system, a computerized dealer system called SEAQ and the automated auction system SETS. Since each new trading system has reduced the level of execution costs, one might expect, a priori, the magnitude of momentum profits to decline with each amendment to the trading system. However, the opposite empirical result is found showing that shares trading on the automated system generate higher momentum profits than those trading on the floor system and companies trading on the SETS system display greater momentum profitability than those trading on SEAQ. Our empirical results concur with the theoretical findings of the trader’s hesitation model of Du [Du, J., 2002. Heterogeneity in investor confidence and asset market under- and overreaction. Working paper] and the empirical findings of Arena et al. [Arena, M., Haggard, S., Yan, X., Price momentum and idiosyncratic volatility. Financial Review, in press].

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A review of the extant literature concludes that market-driven intangibles and innovations are increasingly considered to be the most critical firm-specific resources, but also finds a lack of elaboration of which types of these resources are most important. In this paper, we incorporate these observations into a conceptual model and link it to highly developed institutional settings for the model evaluation. From the point of view of firm revenue management, we can anticipate that performance advantages created through deployment of intellectual and relational capital in marketing and innovation are more likely to be superior. In essence, they constitute the integration of organisational intangibles both in cognitive and behavioural level to create an idiosyncratic combination for each firm. Our research findings show feasible paths for sharpening the edge of market-driven intangibles and innovations. We discuss the key results for research and practice.

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This thesis begins by examining the concepts of civil society and social capital. Specifically, it outlines the role of health and education third sector organisations (TSOs) in building civil society and generating social capital which is conducive to democratisation. Following this, the thesis presents literature on civil society development in the context of the Russian Federation, highlighting a void in our understanding of health and education TSOs in this context. The literature review examines cultural-historic antecedents and their impact on civil society development. These antecedents result in three constraints which limit TSOs ability to establish civil society as an autonomous space. In light of these constraints, the thesis explores the present day realities faced by Russian TSOs and proposes that the all-dominant nature of the Russian state leads to managed civil society arrangements. Consequently the thesis addresses the question of how a managed civil society manifests itself in the context of the Russian Federation. Using a qualitative research design, the thesis investigates the control mechanisms created by legislative framework, the ability of third sector organisations to substitute for the state, and the organisational characteristics of TSOs within a managed civil society space. Based on interview data from 82 TSOs across three geographical regions, the empirical chapters explore these three aspects in-depth. Firstly, the thesis demonstrates how a specific legislative framework is used as a legally mandated method to manage civil society. Secondly, the thesis explores more subtle attempts by the state to manage civil society. And thirdly, the thesis highlights ways in which the state controls TSOs and coerces them to mimic marionette organisations. Overall, the evidence presented throughout the thesis highlights the idiosyncratic nature of managed civil society arrangements in Russia in which the state is able to control and direct civil society

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This research is concerned with the case of Ukraine where there has been a fundamental change in the economic environment engendered by the transition from a centrally planned to a market economy and the resulting conditions of economic crisis. The way that Ukrainian marketers and consumers are reacting to this environmental change is the principal concern of the research together with the basic linkages between critical environmental elements and strategic marketing decisions. This research analyses the way in which marketing evolves in a turbulent, transitional environment. The study is based on eight case analyses within the retail sector of the Ukrainian market. The process of transition to a free market economy leads a researcher to question the validity of existing theories that have been based on empirical data that has been collected in the stable marketing environment of the West. For this reason an in-depth, theory building methodology is preferred. A number of broad research objectives were set. Firstly, to establish whether the sales - production - marketing stages model of marketing evolution, derived from empirical data collected in stable Western environments, is relevant in the context of the turbulent, transitional environment of Ukraine. Secondly, to establish if, in this turbulent, transitional environment, idiosyncratic approaches to marketing are emerging and thirdly to assess the development of attitudes to marketing, organisation for marketing and the development of marketing strategy in Ukraine. The main conclusions of this thesis are firstly, that the stages model of marketing orientation is not relevant in the context of Ukraine, secondly that there are idiosyncratic approaches to marketing emerging in the turbulent, transitional environment of Ukraine and finally that the above developments have a profound impact on the development of attitudes to marketing, organisation for marketing and the development of marketing strategy in Ukraine.