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A new class of forecasting models is proposed that extends the realized GARCH class of models through the inclusion of option prices to forecast the variance of asset returns. The VIX is used to approximate option prices, resulting in a set of cross-equation restrictions on the model’s parameters. The full model is characterized by a nonlinear system of three equations containing asset returns, the realized variance, and the VIX, with estimation of the parameters based on maximum likelihood methods. The forecasting properties of the new class of forecasting models, as well as a number of special cases, are investigated and applied to forecasting the daily S&P500 index realized variance using intra-day and daily data from September 2001 to November 2017. The forecasting results provide strong support for including the realized variance and the VIX to improve variance forecasts, with linear conditional variance models performing well for short-term one-day-ahead forecasts, whereas log-linear conditional variance models tend to perform better for intermediate five-day-ahead forecasts.  相似文献   
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In the presence of an endogenous binary treatment and a valid binary instrument, causal effects are point identified only for the subpopulation of compliers, given that the treatment is monotone in the instrument. With the exception of the entire population, causal inference for further subpopulations has been widely ignored in econometrics. We invoke treatment monotonicity and/or dominance assumptions to derive sharp bounds on the average treatment effects on the treated, as well as on other groups. Furthermore, we use our methods to assess the educational impact of a school voucher program in Colombia and discuss testable implications of our assumptions. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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abstract    In this article we examine project-level and team-level managerial functions aimed at managing inter-team task interdependencies and investigate their effect on the performance of teams in a multi-team product development project. We hypothesize that team interface management (a team-level function) performed in the concept phase of a project, rather than the later development phase, is positively related to team performance at the project's conclusion (i.e. product quality, product cost, development budget, development time). Furthermore, we argue that project structuring and support (a project-level function) is important in both the concept and the development phases. We test our hypotheses empirically based on a 36 months longitudinal study of a product development project in the European automotive industry comprising 39 teams. The results show that team interface management is particularly important during the concept phase of the project. Project structuring and support is most important in the development phase of the project, while hindering team performance in the concept phase. Theoretical and practical implications are discussed.  相似文献   
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Pelikan (J Evol Econ 21:341–366, 2011) develops an interesting conceptual framework that adds to prior work on generalised Darwinism. Despite claims to the contrary we show that it is similar to the approach developed by Hodgson and Knudsen (J Evol Econ 16(4):343–366, 2006a, J Econ Behav Organ 75(1):12–24, 2010ab), Aldrich et al. (J Evol Econ 18(5):577–596, 2008) and others. Pelikan also mischaracterises the Hodgson–Knudsen position over Lamarckism. We show why the term is misleading (rather than strictly wrong) when applied to social evolution.  相似文献   
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This paper develops a contractarian theory of the state and the existence of redistribution. The existence of rules of redistribution is explained without any recourse to the risk-aversion of agents. No veil of ignorance is needed. This avoids obligational problems inherent in most other contractarian theories of justice. Hence, this paper departs from the standard legitimization of redistribution as fundamental insurance and interprets it as stemming from a principle of reciprocity in trade. Since this paper deals with an anarchic society, the implementation of redistributional rules is constrained by the assumption of self-enforcement. We show that this assumption changes the interpretation of the state: the state is characterized by a particular design of equilibrium strategies, not by the existence of enforcement agencies.  相似文献   
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It has been acknowledged that universities are key institutions in national and regional systems of innovation. This recognition has led to a rich stream of literature analysing the university–industry relationship. However, relatively little attention has been devoted to disaggregating the ‘industry’ side of this relationship and examining the costs and benefits to the disaggregated parties involved. In the present article, which draws on an analytical and empirical study from Scotland, it is suggested that it makes sense to distinguish between three kinds of firms in analysing the university–industry relationship: large national and international R&D-intensive firms, university spin-out firms, and established small- and medium-sized enterprises (SMEs) that have had little interaction with universities. The different costs and benefits facing these firms in their interactions with universities are analysed. It is concluded that the established SMEs confront relatively high costs in relating to universities. Finally, the policy implications are explored.  相似文献   
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This paper analyses the fundamental forces involved in the evolution of the telecommunications industry. It is suggested that there are five major forces that together drive the evolution of this industry: specialisation, competition, financial markets. endogenous consumer demand and permeable industry boundaries. An important research task is to further elaborate on the boundaries of not only the industry but of the industrial system taken as a whole.  相似文献   
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