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1.
We study the effect of the educational diversity of managers on the performance of team‐managed mutual funds using a large sample of U.S. equity funds from 1994 to 2013. We consider diversity in terms of both final educational degree and field of educational specialisation. We find that, in general, both types of diversity have a positive impact on fund performance, and our results are robust over a wide range of performance metrics and changes in market conditions.  相似文献   
2.
Drawing upon the research in institutional theory and comparative capitalism, the present study investigates how cross-national differences in the political, business, and economic institutional contexts of the United States, Italy, and Japan are associated with the ways in which companies in each of these countries prioritize and engage in their stakeholder engagement activities (SEAs). Using Porter and Kramer's framework, which classifies corporate social responsibility (CSR) activities as falling into four categories (good citizenship, mitigating harm from value chain, transforming value chain activities, and strategic philanthropy), we investigate how companies in the United States, Japan, and Italy prioritize and engage in these four SEAs. An analysis of data collected from 340 companies across these countries reveals that while companies in each of these three countries undertake the four types of SEAs, the prioritization and prevalence of the four types of SEAs vary from one country to the other, in ways that align with the prevailing institutional contexts of each country. The results contribute to a more nuanced understanding of why and how companies' approaches to CSR differ across countries. From a practitioner's perspective, the findings highlight the cultural specificity of CSR, implying that despite the global nature of CSR, the implementation of CSR needs to be tailored to a country's context.  相似文献   
3.
Luby变换(Luby Transform,LT)码作为信道编码应用于电力线通信(Power Line Communication,PLC),可实现电信号的可靠传输。度分布对LT码编译码性能的影响至关重要。为了得到更优的度分布,首先调整二进制指数分布(Binary Exponential Distribution,BED)中的度数比例,获得一种译码性能更优的改进的二进制指数分布(Improved BED,IBED)。然后,根据IBED在冗余度较小时译码成功率高,而冗余度增大后鲁棒孤子分布(Robust Soliton Distribution,RSD)的译码性能表现更佳的特点,通过求和归一化的方式将IBED与RSD两种度分布的优势进行有机结合,提出一种新型二进制鲁棒孤子分布(Binary RSD,BRSD)。仿真结果表明,与其他方法及传统的RSD相比,采用新度分布进行LT编码,可明显降低译码开销,并节约编译码耗时。将新型度分布应用于基于LT码的PLC系统中,能有效地抑制PLC信道中各种噪声对电信号的干扰,并提高通信效率。  相似文献   
4.
How does the exposure to product market competition affect the investment horizon of firms? We study if firms have an incentive to shift investments toward more short‐term assets when exposed to tougher competition. Based on a stylized firm investment model, we derive a within‐firm estimator using variation across investments with different durabilities. Exploiting the Chinese World Trade Organization (WTO) accession, we estimate the effects of product market competition on the composition of US firm investments. Firms that experienced tougher competition shifted their expenditures toward investments with a shorter durability. This effect is larger for firms with lower total factor productivity.  相似文献   
5.
当前小体积远端射频单元(Remote Radio Unit,RRU)主要是皮站级别的Pico-RRU,其重量和体积仍然难以满足掌上型的要求。为此,采用高集成度的AD9361芯片来实现长期演进(Long Term Evolution,LTE)宽带收发信机功能,配合时钟同步模块、放大器模块和控制接口电路等一起构建低成本的掌上型RRU。主要解决了基于AD9516的时钟同步、低相位噪声设计和高灵敏度接收机设计三个技术难点,成功实现了掌上型、高性能、低成本的设计目标。整个RRU样机尺寸为18 cm×10 cm×2 cm,质量约500 g,量产成本千元以内。测试表明,该RRU下行误差向量幅度(Error Vector Magnitude,EVM)小于3%,优于3GPP要求的8%;10 MHz带宽时上行接收机灵敏度优于3GPP要求的-93.5 dBm。  相似文献   
6.
The present research attempts to qualitatively explore the motivators and barriers of organic food consumption in the Indian context. The data were collected using semistructured in‐depth interviews and analyzed using grounded theory. The theoretical sampling technique was used to interview 34 consumers who have purchased organic food in the past. The findings reported health consciousness, environmental consciousness, social identity, consumer ethnocentrism, and concern for farmers as the factors that motivate organic food purchase among consumers. The factors such as high prices of organic food, unavailability, trust issues, and limited marketing communications from the firms were identified as major barriers to organic food purchase and consumption. The study is one of the initial attempts to qualitatively explore the consumers' motivation for organic food consumption in the Indian context. The findings will help policymakers to devise suitable strategies so that they can effectively target the organic food choices by understanding the motivators/barriers, and promote the sustainable lifestyle in the society, as food consumption plays a crucial role in achieving environmental sustainability.  相似文献   
7.
为了充分利用各种空间设施资源,提升天基信息网络覆盖与传输能力,分别从天基信息网络体系架构和逻辑功能架构角度进行了系统性设计。与以往天基网络的设计不同,该设计更注重各类卫星网络的深度融合应用,为此将网络虚拟化技术引入天基卫星网络。同时,还提出了解决新架构下卫星组网难题的方法,将电磁涡旋、卫星灵活载荷和边缘计算技术设计到天基网络。仿真表明,所提出的架构能有效提升频谱利用率和减少卫星网络信令开销。  相似文献   
8.
Estimation of expected return is required for many financial decisions. For example, an estimate for cost of capital is required for capital budgeting and cost of equity estimates are needed for performance evaluation based on measures such as EVA. Estimates for expected return are often based on the Capital Asset Pricing Model (CAPM), which states that expected excess return (expected return minus the risk-free rate) is equal to the asset's sensitivity to the world market portfolio (β) times the risk premium on the “world market portfolio” (the market risk premium). Since the world market portfolio, by definition, contains all assets in the world, it is not observable. As a result, an estimate for expected return is commonly obtained by taking an estimate for β based on some index (as a proxy for the world market portfolio) and an estimate for the market risk premium based on a potentially different index and multiplying them together. In this paper, it is shown that this results in a biased estimate for expected return. This is undesirable since biased estimates lead to misallocation of funds and biased performance measures. It is also shown in this paper that the straightforward procedure suggested by Fama and MacBeth [J. Financ. Econ. 1 (1974) 43] results in an unbiased estimate for expected return. Further from the analysis done, it follows that, for an unbiased estimate, it does not matter what proxy is used, as long as it is used correctly an unbiased estimate for expected return results.  相似文献   
9.
10.
This paper analyzes the issue costs and initial pricing of bonds in the international market. In particular, we investigate the determinants of three components of issue costs: underwriter fee, underwriter spread (the difference between the offering price and the guaranteed price to the issuer), and underpricing (the difference between the market price and the offering price). Total underwriter compensation increases with the bonds' credit risk and maturity, but it is insignificantly related to issue size. Interestingly, underwriters appear to price some issue characteristics directly (by adjusting the fee) and other characteristics indirectly (by setting the guaranteed price). The two compensation components (fee and spread) are negatively related to each other. We provide evidence that this trade-off is consistent with income tax considerations, as well as with two-tier pricing by underwriters. We find no evidence of underpricing.  相似文献   
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