谈绝对数时间数列的序时平均数的简单算法

作为计算基础的绝对数时间数列的序时平均数在计算时首先分清楚时期数列和时点数列后,其次利用两个间隔时点指标的算术平均数作为连续时点的一般水平后,就可以利用公式直接计算,大大降低了学习难度。     

平均年成本法在固定资产更新决策中的应用及缺陷

固定资产更新决策是在继续使用旧设备和更新新设备之间进行的选择。本文基于平均年成本法的基本原理,阐述平均年成本法在固定资产更新决策中的应用,指出平均年成本法在应用中存在的缺陷。     

2006年,全球风电发展创造记录

2006年,全球风电继续保持快速发展势头,创造了一系列的历史纪录,其中,年新增装机1500万kW,是历史上年新增风电装机容量最多的年份。目前有70多个国家安装了风力发电设施,其中,有13个国家的风电装机容量已超过100万kW。在全球风电装机总容量排名中名列前五位的是德国、西班牙、美国、印度和丹麦,中国列第六位。我国2006年新增风电机组1454台,当年新增装机容量133.7万kW,比过去20年的累计装机总量还要多。到2006年底,全国风电装机容量已达到260万kW,比2005年增长105%。江苏省以单机容量1588kW的高水平起步,居全国平均单机容量的第一位。     

Does job mismatch affect wage earnings among business and management graduates in Vietnam?

This paper investigates the wage penalty resulting from horizontal job mismatch among wage earners with university degrees in the fields of business and management. The study utilizes pooled cross-sectional data from the Labour Force Surveys (LFS) in 2018, 2019 and 2020 in Vietnam. We employ instrumental variable (IV) estimators to address the potential endogeneity of job mismatch. Estimates from the ordinary least square (OLS) and IV methods show that job mismatch has a negative effect on wage earnings and that the penalty for such mismatches is nearly double for men than for women. Also, for mismatched graduates in the private sector, the wage penalty is nearly triple what it is for those in the public sector. Notably, we find that the wage penalty is substantial for those under 50, but less so for those over 50. This suggests that education-specific skills can be substituted by work experience to some extent.     

An Empirical Investigation of the Option-Adjusted Realized Return

The issue of meaningful evaluation of professionally managed portfolios remains to be resolved satisfactorily within the investment community. The fact that many of the current procedures for evaluating portfolio performance are deeply rooted in conventional mean-variance (M-V) analysis raises serious concerns from a theoretical perspective. The primary objective of this paper is an empirical investigation (as differentiated from a thorough empirical test) of an ordinal portfolio performance measure, called the Option-adjusted Realized (average rate of) Return or ORR, developed recently by Smith and Kokoska (1998). The ORR is a leverage- and risk-adjusted average realized rate of return that can be used directly in evaluating portfolio performance.Using returns data for June 1992 to May 1998, we estimate ORRs for two portfolios—the CREF Stock Fund and a hypothetical market index portfolio whose composition is identical to that of the S&P 500 Index. Also, we estimate Sharpe and Treynor ratio values for each portfolio and compare rankings provided by these methods for the two portfolios with rankings provided by the ORR method. For the interval of time from June 1995 to May 1998, the rankings provided by the three methods are not consistent. The ORR rankings for this time period indicate the CREF Fund underperformed the S&P Index on a risk-adjusted basis. Additional partitioning of the data creates other multiple intervals or holding periods for which the evaluation results (ex post) support at least moderate likelihood of unambiguous inconsistency ex ante. We argue that, given our set of assumptions, the ORR rankings, founded in option-pricing theory, are more reliable than the others that are M-V based.     

PREDICTING NEXT TRADING DAY CLOSING PRICE OF QATAR EXCHANGE INDEX USING TECHNICAL INDICATORS AND ARTIFICIAL NEURAL NETWORKS

Accurate prediction of stock market price is of great importance to many stakeholders. Artificial neural networks (ANNs) have shown robust capability in predicting stock price return, future stock price and the direction of stock market movement. The major aim of this study is to predict the next trading day closing price of the Qatar Exchange (QE) Index using historical data from 3 January 2010 to 31 December 2012. A multilayer perceptron ANN architecture was used as a prediction model with 10 market technical indicators as input variables. The experimental results indicate that ANNs are an effective modelling technique for predicting the QE Index with high accuracy, outperforming the well‐established autoregressive integrated moving average models. To the best of our knowledge, this is the first attempt to use ANNs to predict the QE Index, and its performance results are comparable to, and sometimes better than, many stock market predictions reported in the literature. The ANN model also revealed that the weighted and simple moving averages are the most important technical indicators in predicting the QE Index, and the accumulation/distribution oscillator is the least important such indicator. The analysis results also indicated that the ANNs are resilient to stock market volatility. Copyright © 2014 John Wiley & Sons, Ltd.     

Is Beta Dead or Alive?

The debate about whether beta is dead or alive has heated up once again. We believe the empirical work supporting either side of the argument is limited because market frictions are not adequately addressed. This study clarifies the controversy about the issue by creating a new moving-average beta and analyzing two market anomalies: the turn-of-the-year and the Monday effects. What is discovered in this research is (1) that a fundamental source of the problem underlying the two types of market anomalies is the persistence of market frictions that retard the arbitrage process; (2) that beta is seriously ill if the effects of market frictions are ignored; and (3) that beta is alive and well if the effects of market frictions are accommodated. Also, we show, by using an optimal lead/lag structure, the moving-average beta provides significantly higher explanatory power for the turn-of the-year and the Monday effects than betas created from ordinary least squares regression and Scholes-Williams and Fama-French methods because the moving-average beta accommodates the effects of market frictions into the body of beta itself. This new type of beta, a moving-average beta, is demonstrated to be robust.     

中国上市公司资本结构趋势研究

分行业分析了中国A股上市公司1990~2009年资本结构的变化。结果表明:中国A股上市公司资产负债率的行业均值呈递增趋势;不同行业上市公司的资产负债率具有显著差异,资产负债率高(45%~70%)的行业为建筑业、房地产业、批发和零售贸易业、制造业,资产负债率低(22%~45%)的行业为采掘业、交通运输仓储业、社会服务业;新上市公司的资产负债率水平较高,以后年度相对降低,这说明上市公司具有较强的股权融资偏好。最后分析了这一现象产生的原因并提出建议。