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981.
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   
982.
This paper shows that financial constraints of corporate activist investors are negatively perceived by the market. By conducting an event study on a sample of 561 Schedule 13(D) filings disclosed by US corporations in the years 1996–2016, abnormal share price reactions in the [?10, \(+\)3] event window are about 10.8% lower for targets of financially constrained corporate investors. The average abnormal return for all targets is equal to 13.4%. This positive market response suggests that activism results in actual value improvement for the target. Yet, our analyses show that value improvements crucially depend on the investor’s access to external financing.  相似文献   
983.
Using administrative confidential data on the universe of Canadian corporate firms, we compare debt financing choices of private and public firms. Private firms have higher leverage ratios, which are entirely driven by private firms’ stronger reliance on short-term debt. Further, private firms rely more of leverage during economic expansions, while public firms rely on equity financing. Specifically, private firms manage to increase their long-term debt during expansions, while short-term debt is used during downturns. Our findings have implications for a better understanding of the role of asymmetric information in private firms’ capital structure decisions.  相似文献   
984.
We perform peridogram based cycle analysis of firm capital structure and find evidence that firms’ leverage is both persistent and cyclical. The cyclicality of leverage is supported by the trade-off, pecking order and market timing capital structure theories (Korajczyk and Levy in J Financ Econ 68:75–109, 2003; Bhamra et al. in Rev Financ Stud 23:645–703, 2010). Although market timing theory research supports persistence, previous literature dictates that the trade-off and pecking order theories may predict either persistent or mean reverting leverage. Our tests reject mean reversion in favor of persistent and cyclical leverage. We corroborate pecking order theory literature that predicts leverage is persistent. In these models, when firms’ investment spending is below earnings, leverage decreases. In addition, we examine whether firms change their capital structure as a result of business and financial cycles. Since financial cycles last longer than business cycles, financial cycles should have a long term effect on leverage. Our findings confirm the persistent leverage business cycle models that suggest firms change their capital structure due to financial and credit cycles (Jermann and Quadrini in Am Econ Rev 102:238–271, 2012; Azariadis et al. in Rev Econ Stud 83:1364–1405, 2016). We conclude that leverage is persistent due to the cyclicality of the financing decision.  相似文献   
985.
While Open Source Software (OSS) communities provide opportunities for knowledge creation, we have a limited understanding of how entrepreneurs leverage OSS communities for their entrepreneurial ventures. Using social capital theory in a mixed methods case study, we compare entrepreneur and non-entrepreneur behaviors to investigate how entrepreneurs build social capital within an OSS community. This study shows that entrepreneurs differentiate themselves from non-entrepreneurs by focusing on cognitive and relational capital building activities, which in return makes it possible for them to leverage their social capital to influence and shape the environment in which they are operating. Our findings suggest that entrepreneurs strategically select which activities within the community to expend their limited resources on (e.g., developing code over participating in email conversations) and build their social capital more through their actions than through their words (e.g., showing their commitment to the community through code commits, bug fixes, and documentation). Given the liabilities of newness and smallness as well as other challenges faced by entrepreneurs, applying an open innovation strategy in OSS communities could be one approach where entrepreneurs, by developing and freely revealing their intellectual property to the community, share their way to success via OSS-infused entrepreneurial business ventures.  相似文献   
986.

To advance understanding of informal sector entrepreneurship, the aim of this paper is to evaluate and explain the cross-country variations in the prevalence of informal sector competitors. To do so, World Bank Enterprise Survey (WBES) data is reported from 142 countries. This reveals that 27% of formal enterprises view competition from the informal sector as a major constraint on their operations, although this varies from 72% of formal enterprises in Chad to no formal enterprises in El Salvador. To explain these cross-country variations, four competing theories are evaluated which variously view informal sector entrepreneurship and enterprise to be more prevalent when there is either: economic under-development (modernisation theory); high taxes and state over-interference (neo-liberal theory); too little state intervention (political economy theory), or an asymmetry between the laws and regulations of formal institutions and the unwritten socially shared rules of informal institutions (institutional theory). A multilevel probit regression analysis confirms the modernisation and institutional theories, but not the neo-liberal and political theories. Beyond economic under-development, therefore, it is not too much or too little state intervention that is associated with the prevalence of informal sector competition but rather, whether the laws and regulations developed by governments are in symmetry with the norms, values and beliefs of entrepreneurs. The paper concludes by discussing the theoretical and policy implications of these findings.

  相似文献   
987.
The North-America Free Trade Agreement (NAFTA) has brought together the economies of Canada, Mexico, and the US into forming one of the largest trading blocs worldwide (within the top CO2 emitters). However, the current global protectionist discourse threatens the agreement. This paper analyzes the energy and energy-related CO2 emission relationships between NAFTA countries in 2014 to gain insights into the climate change implications of current integration and the possible cancelation of the agreement. The analysis is performed with a multi-regional version of the multi-factor energy input–output model. The results show that NAFTA has not built a single integrated energy system, though it has helped reduce energy-related CO2 emissions. Moreover, if NAFTA is not revoked, further integration would depend on the capacity of the Mexican energy sector to converge to the performance of its trade partners’ energy sectors. Conversely, a broken deal would induce negative environmental externalities.  相似文献   
988.
In the past decade (2000–2010), pirates from Somalia have carried out thousands of attacks on cargo ships sailing through the Gulf of Aden and the Indian Ocean, causing what others have identified as significant damage to maritime trade. In this paper, we use variations in the spread and intensity of Somali piracy to estimate its effect on the volume of international trade. By comparing trade volume changes along shipping routes located in pirate waters to those that are not, we estimate that Somali piracy reduced bulk commodities trade passing through the Gulf of Aden by 4.1% per year from 2000 to 2010. We find smaller reductions in total trade, consistent with the fact that not all goods are shipped by sea or are targets of pirate attacks. While our estimates suggest that the trade costs of piracy are much lower than what has been suggested in the existing literature, we find that they remain significant and unevenly distributed, with five countries and the EU shouldering 70% of the total costs.  相似文献   
989.
990.
This paper builds a model of Schumpeterian innovation and trade that emphasizes endowments of innovators and labor as a key factor in determining the pattern of trade. The model suggests a strong complementarity between intra‐industry and inter‐industry trade. The pattern of inter‐industry vs intra‐industry trade is analyzed using the Grubel–Lloyd index. The theoretical model predicts that the prominence of intra‐industry trade is a nonlinear function of the ratio of the proportion of world knowledge domestically generated to the domestic share of the world labor supply. Strong empirical evidence for this key result is presented and implications are discussed.  相似文献   
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