A Lower Bound for the Wrap-around L2-discrepancy on Combined Designs of Mixed Two- and Three-level Factorials

The objective of this article is to study the issue of employing the uniformity criterion measured by wrap-around L₂-discrepancy to assess the optimal foldover plans. For mixed two- and three-level fractional factorials as the original designs, general foldover plan and combined design under a foldover plan are defined, and the equivalence between any foldover plan and its complementary foldover plan is investigated. A lower bound of wrap-around L₂-discrepancy of combined designs under a general foldover plan is obtained, which can be used as a benchmark for searching optimal foldover plans. Moreover, it also provides a theoretical justification for optimal foldover plans in terms of uniformity criterion.     

中国情境下中层管理者的适应性绩效因素研究

随着我国经济的快速发展和外部竞争的加剧,出现了组织扁平化、企业内外部变化加快和职业高原等新情形,既给中层管理者带来了新困境,也对其适应性提出了新挑战。以Plukos八维度适应性绩效模型为基础,立足国内情景,运用改进型DEMATEL方法对适应性绩效影响因素进行定量分析,得出影响中层管理者适应性绩效的关键因素,并对各因素重要性进行了排序和分析。     

基于突变理论的铀矿山循环经济发展水平评价

铀矿山循环经济发展是铀矿开采的必然选择,铀矿山循环经济发展水平评价是检验和预测循环经济发展状态的判断依据。基于突变理论的改进的突变评价方法,构建了铀矿山循环经济发展水平的评价指标体系,并选取我国核工业某矿冶局所属的5个铀矿山作了铀矿山循环经济发展水平评价的实证分析。实证分析表明了该方法的可行性、有效性和可靠性。这对于铀矿企业处理资源有效利用和环境保护问题,实现经济效益和社会效益协调统一具有理论和现实意义。     

Multiperiod Forecasts of Interest Rates

The accuracy of forecasts of interest rates over different forecast horizons and time periods is examined. The results indicate a deterioration in “absolute” forecast accuracy measured by the mean absolute error and the root mean squared error but no decrease in “relative” accuracy measured by the Theil coefficient with an increase in the forecast span. The results also indicate a decline in accuracy in periods of volatile interest rates. Support is found for the hypothesis that the ratio of the variability of predicted changes to that of actual changes falls with an increase in the forecast horizon.     

A comparison of test statistics for the recovery of rapid growth‐based enumeration tests

This paper considers five test statistics for comparing the recovery of a rapid growth‐based enumeration test with respect to the compendial microbiological method using a specific nonserial dilution experiment. The finite sample distributions of these test statistics are unknown, because they are functions of correlated count data. A simulation study is conducted to investigate the type I and type II error rates. For a balanced experimental design, the likelihood ratio test and the main effects analysis of variance (ANOVA) test for microbiological methods demonstrated nominal values for the type I error rate and provided the highest power compared with a test on weighted averages and two other ANOVA tests. The likelihood ratio test is preferred because it can also be used for unbalanced designs. It is demonstrated that an increase in power can only be achieved by an increase in the spiked number of organisms used in the experiment. The power is surprisingly not affected by the number of dilutions or the number of test samples. A real case study is provided to illustrate the theory. Copyright © 2013 John Wiley & Sons, Ltd.     

An Exposure Assessment of Methyl Mercury via Fish Consumption for the Japanese Population

The objective of this article was to propose an exposure assessment model to describe the relationship between fish consumption and body methyl mercury (MeHg) levels in the Japanese population. Individual MeHg intake was estimated by the summation of species-specific fish consumption multiplied by species-specific fish MeHg levels. The distribution of fish consumed by individuals and the MeHg level in each fish species were assigned based on published data from Japanese government institutions. The probability of MeHg intake for a population was accomplished through a Monte Carlo simulation by the random sampling of fish consumption and species-specific MeHg levels. Internal body MeHg levels in blood and hair were estimated using a one-compartment model. Overall, the mean value of MeHg intake for the Japanese population was estimated to be 6.76 μg/day or 0.14 μg/kg body weight per day (bw/day), while the mean value for the hair mercury level was 2.02 μg/g. Compared with the survey data that tabulated hair mercury levels in a cross-section of the Japanese population, the simulation results matched the hair mercury survey data very well for women, but somewhat underestimated for men and all of the population. This exposure assessment model is a useful attempt at further risk assessment with respect to a risk-benefit analysis.     

An approximation for the hotelling-lawley trace in the noncentral case

A procedure for estimating power in conjunction with the Hotelling-Lawley trace is developed. By approximating a non-central Wishart distribution with a central Wishart, and using McKeon's (1974) F-type approximation, a relatively simple procedure for obtaining power estimates is obtained. The accuracy of the approximation is investigated by comparing the approximate results with those for a wide range of conditions given in Olson's (1973) extensive Monte Carlo study. Siotani's (1971) asymptotic expansion is used to provide further comparative assessments. It is demonstrated that the approximation is of sufficient accuracy to be used in practical applications.     

建设工程项目筹资结构优化

工程项目建设 ,必须要有足够的资金支持 ,面对庞大的资金需求 ,可以从资本市场上寻求投资资金 ,因而如何使筹资结构优化便成为一个重要问题。从筹资方式选择入手 ,分析几种常见筹资手段的特点 ,从中寻求最优筹资结构组合 ,力求避免目前筹资结构单一 ,筹资决策盲目性等问题     

Effects of Feedback Delivery Requirements on Accuracy of Observations

ABSTRACT

Feedback is often used in Organizational Behavior Management to improve employee performance. Accurate feedback results in greater improvements in performance and accurate observations enable accurate feedback. However, employees may find providing feedback to peers aversive. The present study contrived a method to evaluate whether instructing individuals to deliver feedback following observations impacted the accuracy of those observations. Five college-aged participants were exposed to a counterbalanced ABAB design. In the observation-only condition (Condition A) participants conducted observations of confederate posture, scoring whether the confederate’s feet and back were “safe” or “at risk.” In the required-feedback condition (Condition B) participants observed and collected data identically to phase A, but were additionally instructed to deliver feedback regarding confederate postures following each session. The results show that all five participants demonstrated higher accuracy of observations in the observation-only condition. Factors potentially influencing lower accuracy when feedback was required are discussed.     

中印产业内贸易发展水平的指数分析

通过对1993—2009年中印产业内贸易指数的测算,分析中印产业内贸易的发展演变过程和水平,并根据中印两国贸易不平衡的实际情况计算了调整后的产业内贸易指数,从而得出简要的研究结论。