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161.
We study empirically whether nonfinancial firms’ behavior is consistent with systematic risk‐shifting. We compare firms’ operating risk before and after a debt issue, under the assumption that if there is any risk‐shifting it is most likely to occur right after a debt issue. We document a significant increase in firms’ operating risk, even after adjusting for industry influences. The risk‐shifting is higher for firms with no subsequent debt issues, and for firms with lower credit ratings. Other determinants are earnings volatility, size of debt issue, and whether the bond is callable.  相似文献   
162.
We show that highly liquid Exchange‐Traded Funds (ETFs), especially those that are more liquid than their underlying basket of securities (i.e., positive relative liquidity), are particularly attractive to investors. Using three definitions of liquidity, we find that relative liquidity predicts net fund flows, as well as inflows and outflows positively and significantly. We further document a liquidity clientele among institutional investors: (i) relative liquidity is significantly more important for short‐ than for long‐term investors; and (ii) relative liquidity is inversely related to investors’ average holding duration in the ETFs. These two findings provide evidence that relative liquidity encourages short‐term demand.  相似文献   
163.
164.
通过对家庭安全监控系统需求的分析,设计了一种基于ZigBee技术的家庭安全监控系统。分析了家庭安全监控系统的特点,给出了ZigBee网络组建方法和系统的软硬件设计,并介绍了ZigBee网关的实现方法和硬件设计,完成对家庭安全监控系统的搭建。实验验证本系统稳定性强,使用灵活方便,可以实现家庭安全的实时监控,保障家庭安全。  相似文献   
165.
This article investigates the effects of information and communication technologies (ICT) on female labor force participation in a sample of 48 African countries. We specify and estimate linear regression and dynamic panel data models with fixed effects (FE) and system-generalized method of moments (SYS-GMM) estimation over the period 2001–2017. The three main results are that ICT use (mobile phone and internet) significantly stimulates female labor force participation in Africa; this effect is enhanced by financial development and female education; the effect of ICT on female employment in Africa is strongest in the industrial sector. These results remain robust to the provision of social, cultural, and institutional variables.  相似文献   
166.
This paper presents a simple simulation framework for understanding and analyzing vulnerability to stunting. We utilize Demographic and Health Surveys merged with satellite data on climatic shocks. Children aged 0–5 years are grouped into three categories: consistently stunted, vulnerable, and non-vulnerable. The first group constitutes those who are stunted and will also be stunted in any hypothetical period. Non-vulnerable are those whose likelihood to be stunted is zero. The vulnerable face a probability between 0 and 1 of being stunted. The probability is calculated as the share of years in which the child would be stunted, given the village level distribution of weather shocks over the period 2000–2013. We provide estimates of vulnerability to stunting in Burkina Faso, Northern Ghana, Mali, Northern Nigeria, and Senegal by aggregating over villages, districts and countries.  相似文献   
167.
This study investigates whether major USDA reports still provide important news to changing crop markets. The news component of each report, or market “surprise,” is measured as a difference between the USDA estimate and its private expectation in corn, soybeans, and wheat markets. Changes in the relevance of USDA information are assessed by examining changes in the magnitude of market surprises and shifts in the futures price reaction to these surprises, which isolates the impact of each report. The stable size of market surprises over time suggests that competition from alternative data sources has not reduced the news component of USDA crop reports. Increasing price reaction to most reports, including those facing competition from alternative information sources, suggests that value of public information may be enhanced in uncertain markets affected by structural changes.  相似文献   
168.
This paper analyzes the structure of CEO pay in European fixed telecommunication companies, focusing on the impact of state ownership. Results show that, under the (partial or total) control of the state, the level of CEO compensation is lower and pay-performance sensitivity is higher than in privately-controlled firms. This finding suggests the state provides an incentive as well as a monitoring effect. However, when the state holds the majority of the shares, the pay level is significantly affected by the CEO power, suggesting that in these firms, CEOs are more likely to be entrenched with boards and succeed in raising their pay.  相似文献   
169.
Future 5G networks aim at providing new high-quality wireless services to meet stringent and case-specific needs of various vertical sectors beyond traditional mobile broadband offerings. 5G is expected to disrupt the mobile communication business ecosystem and open the market to drastically new sharing based network operational models. 5G technical features of network slicing and small cell deployments in higher carrier frequencies will lower the investment barrier for new entrants to deploy local radio access networks and offer vertical specific services in specific areas and allow them lease the remaining required infrastructure on demand from mobile network operators (MNO) or infrastructure vendors. To realize the full vision of 5G to benefit the society and promote competition, innovation and emergence of new services when the 5G end-to-end network spans across different stakeholders administrative domains, the existing regulations governing the mobile communication business ecosystem are being refined. This paper provides a tutorial overview on how 5G innovations impact mobile communications and reviews the regulatory elements relevant to 5G development for locally deployed networks. This paper expands the recent micro licensing model for local spectrum authorization in future 5G systems and provides guidelines for the development of the key micro licensing elements. This local micro licensing model can open the mobile market by allowing different stakeholders to deploy local small cell networks with locally issued spectrum licenses ensuring pre-defined quality guarantees for the vertical sectors’ case specific needs.  相似文献   
170.
Firm size is known to be an important factor affecting stock returns. This study proposes a panel threshold cointegration model to investigate the impact of the size effect on stock returns for the panel of G7 countries: Canada, France, Germany, Italy, Japan, the U.K., and the U.S. over the period 1991:1–2012:12. The empirical analysis is based upon the nonlinear cointegration framework using the asymmetric ARDL cointegration methodology (Shin et al., 2011). This methodological approach permits a much richer degree of flexibility in the dynamic adjustment process toward equilibrium, than in the classical linear model. Our findings indicate the presence of asymmetric adjustment around a unique long-run equilibrium. In particular, the empirical analysis provides evidence of asymmetric effects between stock returns and the size effect, while controlling for the book-to-market ratio and the price-to-earnings ratio.  相似文献   
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