Power and stability comparisons of multiple testing procedures with false discovery rate control

High-throughput data analyses are widely used for examining differential gene expression, identifying single nucleotide polymorphisms, and detecting methylation loci. False discovery rate (FDR) has been considered a proper type I error rate to control for discovery-based high-throughput data analysis. Various multiple testing procedures have been proposed to control the FDR. The power and stability properties of some commonly used multiple testing procedures have not been extensively investigated yet, however. Simulation studies were conducted to compare power and stability properties of five widely used multiple testing procedures at different proportions of true discoveries for various sample sizes for both independent and dependent test statistics. Storey's two linear step-up procedures showed the best performance among all tested procedures considering FDR control, power, and variance of true discoveries. Leukaemia and ovarian cancer microarray studies were used to illustrate the power and stability characteristics of these five multiple testing procedures with FDR control.     

Linear estimation for the extended exponential power distribution

Tiao and Lund [The use of OLUMV estimators in inference robustness studies of the location parameter of a class of symmetric distributions. J Amer Statist Assoc. 1970;65(329):370–386] tabulated the coefficients of the best linear unbiased estimators (BLUEs) of location and scale for a particular family of symmetric distributions. This family was a reparameterization of the extended exponential power distribution (EEPD) with the shape parameter restricted to be greater than or equal to one. In this work, we consider the BLU estimation of the location and scale parameters of the EEPD when the shape parameter is one-third and one-half. We obtain closed-form expressions for the single and product moments of the order statistics when the shape parameter is in general in the form of a reciprocal of an integer. These expressions are then used to determine the BLUEs and the corresponding variances for complete samples of size 20 and less. We consider some other linear estimators of the location and scale parameters and then compare them with the BLUEs. Finally, we present a numerical example to illustrate the developed results.     

Fitting asymmetric bimodal data with selected distributions

ABSTRACT

This article discusses two asymmetrization methods, Azzalini's representation and beta generation, to generate asymmetric bimodal models including two novel beta-generated models. The practical utility of these models is assessed with nine data sets from different fields of applied sciences. Besides this tutorial assessment, some methodological contributions are made: a random number generator for the asymmetric Rathie–Swamee model is developed (generators for the other models are already known and briefly described) and a new likelihood ratio test of unimodality is compared via simulations with other available tests. Several tools have been used to quantify and test for bimodality and assess goodness of fit including Bayesian information criterion, measures of agreement with the empirical distribution and the Kolmogorov–Smirnoff test. In the nine case studies, the results favoured models derived from Azzalini's asymmetrization, but no single model provided a best fit across the applications considered. In only two cases the normal mixture was selected as best model. Parameter estimation has been done by likelihood maximization. Numerical optimization must be performed with care since local optima are often present. We concluded that the models considered are flexible enough to fit different bimodal shapes and that the tools studied should be used with care and attention to detail.     

Uncertainty and Variability in Health-Related Damages from Coal-Fired Power Plants in the United States

The health‐related damages associated with emissions from coal‐fired power plants can vary greatly across facilities as a function of plant, site, and population characteristics, but the degree of variability and the contributing factors have not been formally evaluated. In this study, we modeled the monetized damages associated with 407 coal‐fired power plants in the United States, focusing on premature mortality from fine particulate matter (PM_2.5). We applied a reduced‐form chemistry‐transport model accounting for primary PM_2.5 emissions and the influence of sulfur dioxide (SO₂) and nitrogen oxide (NO_x) emissions on secondary particulate formation. Outputs were linked with a concentration‐response function for PM_2.5‐related mortality that incorporated nonlinearities and model uncertainty. We valued mortality with a value of statistical life approach, characterizing and propagating uncertainties in all model elements. At the median of the plant‐specific uncertainty distributions, damages across plants ranged from $30,000 to $500,000 per ton of PM_2.5, $6,000 to $50,000 per ton of SO₂, $500 to $15,000 per ton of NO_x, and $0.02 to $1.57 per kilowatt‐hour of electricity generated. Variability in damages per ton of emissions was almost entirely explained by population exposure per unit emissions (intake fraction), which itself was related to atmospheric conditions and the population size at various distances from the power plant. Variability in damages per kilowatt‐hour was highly correlated with SO₂ emissions, related to fuel and control technology characteristics, but was also correlated with atmospheric conditions and population size at various distances. Our findings emphasize that control strategies that consider variability in damages across facilities would yield more efficient outcomes.     

工匠精神融入大学生职业信念培育的探讨

工匠精神是一种包含了爱岗敬业、精益求精、执着专注、追求卓越等一系列良好品格的精神集合体,蕴涵了包括职业文化、职业信念和职业道德等方面的要求,工匠精神与职业信念高度契合。工匠精神融入大学生职业信念培育,有助于加快建设制造强国、丰富高校思想政治教育的内容、培养时代新人以及弘扬并践行社会主义核心价值观。应坚持社会主义核心价值观导向、精神渗透、三结合、外化于行等原则。具体途径有坚持主渠道,渗透工匠精神,增强职业认同;引导职业规划,定位工匠精神,培养职业情感;加强文化熏陶,感悟工匠精神,提升职业自信;开展专业实践活动,体验工匠精神,强化职业意志。     

Strategic Supply Function Competition With Private Information

A finite number of sellers (n) compete in schedules to supply an elastic demand. The cost of each seller is random, with common and private value components, and the seller receives a private signal about it. A Bayesian supply function equilibrium is characterized: The equilibrium is privately revealing and the incentives to rely on private signals are preserved. Supply functions are steeper with higher correlation among the cost parameters. For high (positive) correlation, supply functions are downward sloping, price is above the Cournot level, and as we approach the common value case, price tends to the collusive level. As correlation becomes maximally negative, we approach the competitive outcome. With positive correlation, private information coupled with strategic behavior induces additional distortionary market power above full information levels. Efficiency can be restored with appropriate subsidy schemes or with a precise enough public signal about the common value component. As the market grows large with the number of sellers, the equilibrium becomes price‐taking, bid shading is on the order of 1/n, and the order of magnitude of welfare losses is 1/n². The results extend to inelastic demand, demand uncertainty, and demand schedule competition. A range of applications in product and financial markets is presented.     

论表见代理中的本人过错

表见代理的主要民法功能在于对交易安全和对交易人信赖利益的保护,我国民事法律对表见代理的构成要件没有规定具体的标准,本人的过错能否作为表见代理的必要构成要件,理论界一直有争论。本文全面分析表见代理中本人过错的立法基础和民法价值、以及存在的各种形态,认为有必要在未来立法时,将本人的过错作为表见代理成立的必要条件,以纠正表见代理认定上的纷争和混乱。     

冀南抗日根据地政权研究

冀南抗日根据地是中国共产党在抗日战争时期建立的根据地。在艰苦复杂的抗战局面下,冀南抗日根据地建立了＂三三制＂的根据地政权,发展人民民主,高度重视基层政权的建设和改造,坚持在特定历史时期中国共产党的绝对领导。其行政机关、权力机关、司法机关运转有效,在组织、政策、运作等各方面都颇具特色。     

电影与国家形象:产业、文化与美学

所谓国家形象,是一个国家的经济、政治、军事、文化、人口、历史、民族等方面的表象特征的总和,是通过大众传媒、影视产品等传播介质所塑造出的形象。它既包括一个国家在国内的形象,也包括在国外的形象。在全球信息和市场流通的前提下,一个国家的国际形象和国内形象之间往往相互参照、相互影响、相互作用。西方国家对中国形象的认知随着时代的变化也经历了一个不断变化的过程。直到20世纪,西方的中国形象仍表现出两个极端,而在文化的功能上则表现为西方文化的"他者"形象。国家文化形象是国家形象的重要组成部分,具有独特的价值和意义。中国电影自其诞生之日起,一方面要保障自身健康发展,同时又要承担起塑造国家形象的使命。文化自觉和文化自信是电影产业发展的前提,也是电影产业塑造中国国家形象的关键,只有如此,才能改变当下中国国家形象"他塑"的局面。