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61.
This paper derives and analyzes the selectivity and market timing performance of the mutual funds for the Turkish economy for the financial crisis period by employing high-frequency data. The determinants of these derived abilities are investigated within a regression analysis. The results suggest weak evidence about selection ability and some evidence about superior market timing quality. They also indicate that management fees are negatively correlated with the ability measure, which is quite surprising. Experience emerges as an important factor, especially for market timing ability.  相似文献   
62.
针对宽带短波通信正交频分复用(OFDM)系统,提出了一种不需要数据辅助的高效符号定时同步方法。该方法利用OFDM符号中的空载波不传输任何数据这一特性,通过最小化空载波上的数据能量来将符号定时点锁定在安全区域内,从而完成符号定时同步。该方法可以有效对抗多径效应,适用于短波通信系统。最后将该方法与Al-Dweik同步方案在宽带短波信道条件下进行了仿真对比,结果表明该方法有着更精确的符号定时同步性能,并且适用于各种星座图调制。  相似文献   
63.
针对正交频分复用(OFDM)系统对同步错误率和频率偏移敏感的问题,提出了一种叠加共轭对称训练序列的OFDM系统时间和频率同步方法。该同步方法将快速傅里叶逆变换(IFFT)调制后的序列构成具有共轭对称特性的训练序列,并叠加到OFDM数据符号上;在接收端,利用叠加训练序列和融合循环前缀信息来获取OFDM系统同步信息。理论分析和仿真表明:在信噪比为5 dB时,该同步算法定时同步正确概率已接近100%;在信噪比为4 dB时,频偏估计精度可以达到10-4;该同步算法不仅具有更好的同步性能,而且节省系统的有效带宽以及降低系统的计算法复杂度。  相似文献   
64.
LTE(Long Term Evolution)系统中,作为小区搜索的第一步,符号定时算法需要具备很强的鲁棒性。为了进一步增强现有符号同步算法的抗频偏性能,提出了一种优化的符号同步算法。该算法一方面保持已有分段相关同步算法的优点,同时考虑结合预频偏处理来进行符号定时与粗频偏的联合估计,再将多个相关运算集做叠加处理。理论分析和仿真实验结果表明,在多径信道下,所提算法在完成符号定时和粗频偏估计的同时,大大提高了系统抗频偏性能。  相似文献   
65.
发展绿色经济推进经济转型是实现科学发展的核心。市场自身转型的滞后是影响绿色经济发展的重要因素。转型具有公共物品的性质,公共财政的本质意味着政府介入从而消除滞后的合意性。绿色新技术采用的滞后是造成转型滞后的关键,新技术采用路径的均衡时间受多种因素影响从而滞后的程度也就不同;但均衡时间的比较静态分析结果表明,新技术创新的强度、市场需求、贴现率、技术采用成本、既有生产成本以及企业行为等因素的改变都会影响均衡的采用时间,这些都为政府的介入提供了基础。  相似文献   
66.
风险投资是专业化投资过程,IPO是参与各方首选退出方式。我国风险投资起步晚、发展缓慢,基于发达国家资本市场得出的有关风险投资的结论未必适用于我国。本文使用深交所中小板相关数据检验风险投资在我国风险企业IPO过程中的具体作用,并对检验结果进行分析。通过对风险投资与风险企业IPO关系研究,为我国风险投资的发展提出合理化建议。  相似文献   
67.
Stock options are one of the most widely used equity-based compensation mechanisms to mitigate misalignment between managers’ and shareholders’ interests. And yet, it is sometimes suspiciously used as a method of extracting shareholders’ wealth to managers (Bebchuk et al., 2009). The typical ways to do so is using opportunistic timing such as backdating, spring-loading, etc. As shown in Bebchuk et al. (2010), opportunistic timing of option grants increases the incidence of lucky grants, or stock option grants that CEOs receive when the price is abnormally low. We investigate whether lucky grants to CEOs impact firm innovations and, by extension, long-term growth. Using patent citations as a proxy variable for innovation (Kogan et al., 2017), we find that innovation decreases if CEOs received lucky grant in the previous year. The results imply that lucky grants may reduce the incentive for CEOs to invest in risky, long-term projects and negatively affect fir innovation.  相似文献   
68.
We study how producers of cultural goods can strategically invest in raising the attractiveness of their goods in order to secure the most profitable release dates. In a game‐theoretic setting, where two producers choose their investment expenditure before simultaneously setting the release date of their good, we prove that two equilibria are possible: releases are either simultaneous (at the demand peak) or staggered (one producer delays). In the latter equilibrium, the first‐mover secures its position by investing more in attractiveness. We test this prediction on a dataset of more than 1500 American movies released in 10 countries over 12 years. Results are consistent with the theoretical predictions, indicating that higher budget movies are released closer to seasonal demand peaks.  相似文献   
69.
We provide evidence that managers and controlling shareholders time management buyouts (MBOs) and freezeout transactions to take advantage of industry-wide undervaluation. Portfolios of industry peers of MBO and freezeout targets show significant alphas of around 1% per month over the 12-month period following the transaction. These returns are not explained by a battery of risk factors or empirical methodologies, but exhibit significant heterogeneity across deals. Additional tests show that, on average, abnormal returns to industry peers are a reliable proxy for those to the target firm. Further, MBOs and freezeouts are announced during troughs of industry profitability.  相似文献   
70.
In this paper, we explore the conditions of entry‐timing advantages in renewable natural resource industries. Drawing from behavioural theory of the firm, we classify firms in two groups depending on the different heuristics used to make entry decisions when facing the cyclical endogenous nature of these industries: crowd firms are procyclical, making decisions based on the current phase of the industry cycle, whereas anti‐crowd firms follow a countercyclical strategy, making uncertain, and risky decisions by estimation of the next phase of the cycle. Therefore, anti‐crowd firms anticipate the deployment of resources each cycle, potentially gaining entry‐timing advantages beyond those provided by traditional competitive isolating mechanisms. Through a mathematical simulation of a performance feedback model, we reveal that the entry‐timing advantage of the anti‐crowd group becomes possible when the rivalry in the industry and the price sensitivity of competitors are high, and when the time required to deploy the resources is short.  相似文献   
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