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61.
62.
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   
63.
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   
64.
Addressing environmental, social and governance (ESG) issues has become a critical part of business strategy. This article explores the extent of ESG reporting of metal and mining sector companies listed in the Australian Securities Exchange to determine the nature of ESG indicators in use in the sector. The current study argues that stakeholder engagement is the key to enhance company environmental policy and sustainable development. According to the results of this study, ESG reporting motives are highly influenced by reporting regulations. Given the diversity in reporting of ESG, comparability of ESG strategic performance is problematic. This study contributes towards developing an ESG disclosure index, which companies could use as a legitimacy tool that external stakeholders could use to reliably measure and compare the ESG performance of companies. It also reveals there is an increased demand for more empirical research on integration of sustainability into strategic planning process. Copyright © 2016 John Wiley & Sons, Ltd and ERP Environment  相似文献   
65.
We examine aggregate consumption growth predictability. We derive a dynamic consumption equation which encompasses relevant predictability factors: habit formation, intertemporal substitution, current income consumption and non‐separabilities between private consumption and both hours worked and government consumption. We estimate this equation for a panel of 15 OECD countries over the period 1972–2007, taking into account parameter heterogeneity, endogeneity and error cross‐sectional dependence using a GMM version of the common correlated effects mean group estimator. Small‐sample properties are demonstrated using Monte Carlo simulations. The estimation results support income growth as the only variable with significant predictive power for aggregate consumption growth. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
66.
In this study, we examine the effect of mutual fund connections, through managerial sharing, on performance and stock holding commonalities. Our analysis of return correlations and portfolio holdings indicates that more interconnected funds tend to buy and sell similar stocks, hence increasing the similarity of portfolio holdings and undermining the distinctiveness of their investment strategy. Our results also indicate that highly connected funds significantly underperform weakly connected funds by about 1.4% on a yearly risk‐adjusted basis. We show that fund family performance is unaffected by the intensity of fund connections, and that greater fund connections could significantly enhance family‐level profit margins.  相似文献   
67.
This paper investigates the effect of nearby nature substitute sites on preferences for nature restoration. Contrary to prior studies, we use a respondent-centric approach to control for substitute sites. We assess each respondent-specific spatial context by computing densities of nature substitute sites within various ranges from each respondent’s home. This approach considers the use and non-use values of nature together. Data from three similar discrete choice experiments carried out in Flanders (Belgium) are compared. Different spatial discounting factors are tested to explore how the substitution effect behaves with regard to distance. Latent class analyses are performed to account for preference heterogeneity among respondents. We observe divergent behaviours across groups of respondents. The “distance-to-substitutes” affects how respondents gauge substitute sites. We find a significant influence of the squared average buffer distance but this effect varies in sign across case studies and classes of respondents. Our results demonstrate that individual-specific GIS data can significantly improve the representation of the spatial context and the transferability of value functions. However, the roles played by preference heterogeneity and nature perception on respondents’ capacity to value nature still deserves further attention in future research.  相似文献   
68.
This article assesses the consistency between Indonesia’s National Labour Force Survey (Sakernas) and the Indonesia Family Life Survey (IFLS) for analyses of the country’s labour market. I show that Sakernas and the IFLS depict different levels of and changes in labour-market indicators. My estimates of the labour-force participation model, the sector-choice model, and the Mincer model are all statistically different between the two surveys, although the magnitudes are similar for labour-force participation and sector choice. The IFLS shows a much higher return to education than Sakernas, according to the Mincer model. In addition, I find that the cross-sectional sample of the IFLS and the panel sample of the IFLS corrected for attrition yield similar coefficient estimates from all equations. The findings in this article provide an important reference for researchers interested in using Sakernas and the IFLS—either individually or combined—to analyse labour-market issues in Indonesia.  相似文献   
69.
Individuals, differing in productivity and life expectancy, vote over the size and type of a collective annuity. Its type is represented by the fraction of the contributive (Bismarckian) component (based on the worker's past earnings) as opposed to the non‐contributive (Beveridgean) part (based on average contribution). The equilibrium collective annuity is either a large mostly Bismarckian program, a smaller pure Beveridgean one (in accordance with empirical evidence), or nil. A larger correlation between longevity and productivity, or a larger average life expectancy, both make the equilibrium collective annuity program more Beveridgean, although at the expense of its size.  相似文献   
70.
The concepts of isotropy/anisotropy and separability/non‐separability of a covariance function are strictly related. If a covariance function is separable, it cannot be isotropic or geometrically anisotropic, except for the Gaussian covariance function, which is the only model both separable and isotropic. In this paper, some interesting results concerning the Gaussian covariance model and its properties related to isotropy and separability are given, and moreover, some examples are provided. Finally, a discussion on asymmetric models, with Gaussian marginals, is furnished and the strictly positive definiteness condition is discussed.  相似文献   
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