An approximate degrees of freedom test for heteroscedastic two-way ANOVA

Heteroscedastic two-way ANOVA are frequently encountered in real data analysis. In the literature, classical F-tests are often blindly employed although they are often biased even for moderate heteroscedasticity. To overcome this problem, several approximate tests have been proposed in the literature. These tests, however, are either too complicated to implement or do not work well in terms of size controlling. In this paper, we propose a simple and accurate approximate degrees of freedom (ADF) test. The ADF test is shown to be invariant under affine-transformations, different choices of contrast matrix for the same null hypothesis, or different labeling schemes of cell means. Moreover, it can be conducted easily using the usual F-distribution with one unknown degree of freedom estimated from the data. Simulations demonstrate that the ADF test works well in various cell sizes and parameter configurations but the classical F-tests work badly when the cell variance homogeneity assumption is violated. A real data example illustrates the methodologies.     

当前大学生就业歧视的经济分析

当前大学生就业问题日益严重,用人单位的就业歧视行为,如学历歧视和院校歧视等也愈演愈烈。经济分析使我们了解到,由于劳动力市场信息不对称,从而导致用人单位将学历和文凭视为市场信号,因而用人单位的学历歧视和院校歧视行为并非盲目的非理性行为,而是符合“经济人”假设的理性行为。     

电视信号的加解扰

随着有线电视技术的飞速发展,有线电视用户迅猛增加,而系统的管理落后、上门收费被动,给有线电视经营者带来困扰,需要行之有效的措施来抵制不交费的用户。同时,随着有线电视向宽带多功能综合网发展,每个用户有不同的服务要求。因此,迫切需要研制出先进的加解扰技术,建立一个标准化、规范化、适合我国国情的有线电视新型网络。     

基色编码器的信号设计(英文)

在0{R,G,B}1条件下,推导出了一组用于电视基色编码器的信号设计公式,可以满足不同电视测试信号类型和编码方式的要求。这种可编程控制的设计技巧今后能够被用来作为电视测试信号发生器的首选新方法。     

On the construction of Bayes–confidence regions

We obtain approximate Bayes–confidence intervals for a scalar parameter based on directed likelihood. The posterior probabilities of these intervals agree with their unconditional coverage probabilities to fourth order, and with their conditional coverage probabilities to third order. These intervals are constructed for arbitrary smooth prior distributions. A key feature of the construction is that log-likelihood derivatives beyond second order are not required, unlike the asymptotic expansions of Severini.     

论美感增力性的生理和心理基础——美育科学化原理研究之一

美感的产生有着深刻的生理和心理原因,因而才能以其显著的增力性激发着人们去追求、去创造。美感增力性的生理基础具有强度适中和第二信号系统支持的特征;其心理基础在于美感合乎人的心理需要和人的充分创造性的本质,决定了它在人的精神生活中无所不在。要科学地建构和实施美育,还必须对有关问题作进一步的实验验证     

非媒体信息、非媒体机构与大众传媒的有限功能——兼及一种去媒体中心化的舆论监督观

由于信息类型的多样性与社会分工的多元化,不论是在环境监测还是在舆论监督中,我们都不能对大众媒体寄予太多的期望.对媒体功能的分析不能忽视两个事实:一是媒体只是社会信息传播系统中的一个组成部分,只承担了一部分的信息传播功能;第二,媒体的能力是有限的,它无法呈现全部的信息,其洞察、监督及信息收集与分析能力都有很大的局限性.通过区分媒体信息与非媒体信息、媒体信息机构与非媒体信息机构,我们可以客观地审视其社会功能.正如大众传媒的有限效果一样,大众传媒的功能也是有限的,受其他社会装置的制约.若从舆论监督的角度看,没有其他“非舆论监督”机制或机构的配合,大众传媒的舆论监督必然事倍功半,即便在最为民主的体制下也是如此.     

一种非正交多址接入下行链路信号检测方法

非正交多址接入（non-orthogonal multiple access,NOMA）下行链路存在严重的多址干扰。软解调-串行干扰消除（successive interference cancellation,SIC）检测方法是一种性能较好的信号检测方法,但是接收机的复杂度比较高。考虑到软解调算法对其他用户信号的信号特征信息并未充分利用,提出一种基于软解调算法改进的联合检测算法,该算法直接利用多用户叠加信号的联合星座图计算用户信号信息比特的软信息,不需要对干扰信号进行检测和重构,可以降低接收机的复杂度。仿真分析表明,与软解调-SIC检测方法相比,联合检测方法在性能损失不超过1．5 dB的情况下,可以将接收机的复杂度降低一半。     

基于信号博弈的中外资银行信贷竞争行为分析

在银行业全面开放及贷款利率市场化条件下,异,对中外资银行信贷舍约竞争行为的影响。结果表明：本文利用信号博弈模型,讨论了信息差异及经营成本差1）中资银行的竞争优势是老借款人。2）外资银行提供分离合约时,在中资银行的新借款人市场上将出现“柠檬效应”;外资银行提供混同合约时,中资银行将失去所有新借款人。     

Bayesian inference for a flexible class of bivariate beta distributions

Several bivariate beta distributions have been proposed in the literature. In particular, Olkin and Liu [A bivariate beta distribution. Statist Probab Lett. 2003;62(4):407–412] proposed a 3 parameter bivariate beta model which Arnold and Ng [Flexible bivariate beta distributions. J Multivariate Anal. 2011;102(8):1194–1202] extend to 5 and 8 parameter models. The 3 parameter model allows for only positive correlation, while the latter models can accommodate both positive and negative correlation. However, these come at the expense of a density that is mathematically intractable. The focus of this research is on Bayesian estimation for the 5 and 8 parameter models. Since the likelihood does not exist in closed form, we apply approximate Bayesian computation, a likelihood free approach. Simulation studies have been carried out for the 5 and 8 parameter cases under various priors and tolerance levels. We apply the 5 parameter model to a real data set by allowing the model to serve as a prior to correlated proportions of a bivariate beta binomial model. Results and comparisons are then discussed.