THE STATISTICS OF LONG-HORIZON REGRESSIONS REVISITED1

This paper compares commonly used approaches for estimating the relation between long-horizon returns and a predetermined variable X₁, such as dividend yields. Specifically, we look at regression of (i) nonoverlapping multiperiod returns on X_t (ii) overlapping multiperiod returns on X_t, (iii) single-period returns on multiperiod X_t, and (iv) single-period returns on X_t and its implied long-horizon regression coefficient. We provide analytical formulae which quantify the efficiency of the estimators used in the various approaches. Using the formulae, as well as Monte Carlo simulations, we demonstrate that the relative efficiency of the estimators used in the various approaches differs remarkably, depending on the dynamic structure of the regressor. of special interest for financial economists, when the regressors are highly autocorrelated, we find that the regressions (ii) (iii), and (iv) provide only marginal efficiency gains above and beyond the nonoverlapping long-horizon regression.     

一种新的OFDM同步跟踪技术及其在VHF/UHF通信系统中的应用

本文主要研究了我国加工贸易领域信息化管理的系统组成和发展状况,通过深入分析加工贸易的业务流程、信息化管理特点、发展困惑等内容,提出了优化加工贸易信息化管理的相关举措。     

小仰角下移动卫星通信性能的改善及仿真

移动卫星通信系统为功率受限系统,相对地面移动通信而言,其链路余量较小,而且由于多径及遮蔽效应,当系统工作在小仰角时,其信号衰落可达到30dB,这对系统的设计提出了严峻的挑战。本文研究了信道编码和交织技术在移动卫星通信系统中的应用。通过仿真,得到了应用该技术对不同仰角特别是小仰角条件下系统性能的改善程度。同时,在研究信道相关的基础上,给出了交织相关参数的设计准则。     

关于汉语/英语AMR语音编码参数统计特性的研究

自适应多速率（AMR）算法是第三代移动通信系统中语音业务所采用的语音编码标准。为研究AMR算法应用于汉语语音和英语语音所产生的差异，本文针对ARM语音编码算法的特点，在处理分析了大量汉语语音数据的基础上，对算法中的线谱频率（LSF）、基音周期等关键编码参数进行了比较并给出相应结合。本文的研究有助于AMR算法针对汉语语音的性能优化。     

Hyperbolic Efficiency and Parametric Distance Functions: With Application to Spanish Savings Banks

Distance functions are gaining relevance as alternative representations of production technologies, with growing numbers of empirical applications being made in the productivity and efficiency field. Distance functions were initially defined on the input or output production possibility sets by Shephard (1953, 1970) and extended to a graph representation of the technology by Färe, Grosskopf and Lovell (1985) through their graph hyperbolic distance function. Since then, different techniques such as non parametric-DEA and parametric-SFA have been used to calculate these distance functions. However, in the latter case we know of no study in which the restriction to input or output orientation has been relaxed. What we propose is to overcome such restrictiveness on dimensionality by defining and estimating a parametric hyperbolic distance function which simultaneously allows for the maximum equiproportionate expansion of outputs and reduction of inputs. In particular, we introduce a translog hyperbolic specification that complies with the conventional properties that the hyperbolic distance function satisfies. Finally, to illustrate its applicability in efficiency analysis we implement it using a data set of Spanish savings banks.     

Computer-assisted hospitality information systems

Within the last decade a vast array of computerized management information systems have become available to the hospitality industry. Their impact has not so far been significant, but where they have been introduced efficiency has increased, employees have gained greater professionalism and job satisfaction and cost effectiveness has improved.     

Market efficiency in Scandinavian racetrack betting

This study analyzes Scandinavian racetrack betting markets. We discuss market efficiency and investor behavior in light of the fact that investors earn negative returns on average. Show bets on favorites in Norway yield a small positive return, while all the other betting markets are weak form efficient. We establish the favorite-longshot bias for quinella and exactor bettors, but not for win bettors. Our results can be explained by small pools and high track takes. Investors wagering at the racetrack have a different risk attitude than investors wagering off the track. We explain how our results should influence the design of betting products, especially with respect to the fraction of the pool returned to winners.     

The determinants of short selling: evidence from the Hong Kong equity market

While most financial regulators agree that short sellers have an important role to play in ensuring an efficiently functioning market, it is interesting to note that many did not hesitate to ban short selling during the recent financial crisis. This apparent contradiction most likely stems from a lack of understanding about what motivates short trading. In this paper, we focus on the determinants of short selling during ‘normal’ trading in the Hong Kong stock market. We find that dividend payments, company fundamentals, risk, option trading, the interest rate spread and past returns and short selling are all significant determinants of short selling.     

我国会计师事务所效率的实证研究——基于中注协2008—2010年发布数据

运用DEA数据包络和Malmquist生产力指数相结合的方法,综合考虑投入和产出以及它们之间的关系,对我国会计师事务所行业2007至2009年的效率变动进行实证研究;实证了会计师事务所投入要素的使用效用具有波动性,在经营管理上存在投入成本的浪费,技术效率变动为正增长,总的生产力水平在逐渐下降;事务所管理层可以通过控制并即时调整、优化和整合有效资源,加强技术创新的投入,实现规模经济效益,提升市场竞争力。     

税收有效性、征税权归属与宪法性约束

税收的有效性一方面蕴含着效率、公平与稳定的积极职能,另一方面包含着对产权结构的效益负责的消极职能。税收有效性由国家征税权负责实施,征税权归属构成税收有效性的政治基础,征税权代议制由于在其内部结构中设置了平衡机制而成为实践税收有效性的现代制度基石。伴随着政治结构中利益集团的成型,征税权代议制导致多数联盟对少数者的歧视与强占,为确保税收有效性,需要从程序和实体两个侧面对征税权施加外在的宪法性约束。