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81.
Default Risk in Equity Returns   总被引:17,自引:0,他引:17  
This is the first study that uses Merton's (1974) option pricing model to compute default measures for individual firms and assess the effect of default risk on equity returns. The size effect is a default effect, and this is also largely true for the book‐to‐market (BM) effect. Both exist only in segments of the market with high default risk. Default risk is systematic risk. The Fama–French (FF) factors SMB and HML contain some default‐related information, but this is not the main reason that the FF model can explain the cross section of equity returns.  相似文献   
82.
Maria L Nathan 《Futures》2004,36(2):181-199
Foresight is rooted in deep understanding [A.N. Whitehead. Lecture notes from address to the Harvard Business School, 1931]. Such understanding requires that we shall have first looked back to the past before venturing forward into the future. This paper uses Weick’s and colleagues’ sense making perspective in order to explore this critical relationship between the past and the future [[2], [3], [4], [5], [6] and [7]]. In particular, key sense making properties will be applied to a crisis, an occurrence of school-place violence that occurred in the United States in 1999. We shall then ask how this organization and its diverse external stakeholders used their understanding of this event to learn how to prevent such crises from occurring in the future. In other words, how capably was hindsight constructed and then how was it used to strengthen foresight into the future? This paper will conduct a theory-based empirical examination of a crisis event and its aftermath to understand how hindsight can be sharpened and then used to improve organizational foresight.  相似文献   
83.
Medicaid is a government programme that also provides health insurance to the elderly who have few assets and either low income or catastrophic health care expenses. We ask how the Medicaid rules map into the reality of Medicaid recipiency, and we ask what other observable characteristics are important to determine who ends up on Medicaid. The data show that both singles and couples with high retirement income can end up on Medicaid at very advanced ages. We find that, conditioning on a large number of observable characteristics, including those that directly relate to Medicaid eligibility criteria, single women are more likely to end up on Medicaid – so are non‐white people, but, surprisingly, their higher recipiency is concentrated in the higher income percentiles. We also find that people with low incomes who have a high‐school diploma or higher degree are much less likely to end up receiving Medicaid than their less‐educated counterparts. All of these effects are large and depend on retirement income in a very non‐linear way.  相似文献   
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85.
While univariate nonparametric estimation methods have been developed for estimating returns in mean-downside risk portfolio optimization, the problem of handling possible cross-correlations in a vector of asset returns has not been addressed in portfolio selection. We present a novel multivariate nonparametric portfolio optimization procedure using kernel-based estimators of the conditional mean and the conditional median. The method accounts for the covariance structure information from the full set of returns. We also provide two computational algorithms to implement the estimators. Via the analysis of 24 French stock market returns, we evaluate the in-sample and out-of-sample performance of both portfolio selection algorithms against optimal portfolios selected by classical and univariate nonparametric methods for three highly different time periods and different levels of expected return. By allowing for cross-correlations among returns, our results suggest that the proposed multivariate nonparametric method is a useful extension of standard univariate nonparametric portfolio selection approaches.  相似文献   
86.
ABSTRACT

Infrastructure is commonly conceptualized as a set of facilities that play a critical role in facilitating activities by individuals and organizations. Conventionally, infrastructure is tightly linked to publicly funded projects that facilitate access to key resources and enable diverse activities. Within entrepreneurial clusters research, infrastructure includes universities, research institutions and telecommunication technologies that facilitate entrepreneurial activities. These capital-intensive investments seek to facilitate start-ups emergence by aiding access to markets and development of ideas. Accelerators facilitate the same activities and have only recently been conceptualized as start-up infrastructure. This study builds upon this research stream by elaborating on how accelerators can play this meaningful role at the cluster level. Specifically, and by relying on the analysis of empirical evidence from three distinct studies, we uncover how accelerators provide tangible and intangible dimensions of start-up infrastructure to form a positively reinforcing cycle of entrepreneurial activities. Additionally, our findings allow us to push further the idea that start-up infrastructure development can be an endogenous process involving multiple actors within the cluster. Our empirical findings and the theoretical insights derived from them have meaningful implications for the aforementioned literature, as well as start-up practitioners and policymakers linked to the funding of entrepreneurial clusters.  相似文献   
87.
Quality & Quantity - Compositional data with a tridimensional structure are not uncommon in social sciences. The CANDECOMP/PARAFAC model is one of the most adequate techniques for modeling...  相似文献   
88.
论旅游学研究的对象和任务   总被引:1,自引:0,他引:1  
从旅游学产生的历史和旅游学理论体系的内容两个角度对旅游学的研究对象进行了分析研究,认为旅游学的研究对象就是旅游活动和旅游业,其中又以旅游的三要素——旅游主体、旅游客体、旅游媒体及其相互关系为核心。其任务是找出对旅游活动和旅游业发展的规律性认识,对旅游实践活动起到理论上的指导作用  相似文献   
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