Data Dependent Cells Chi‐Square Test With Recurrent Events

We consider a recurrent event wherein the inter‐event times are independent and identically distributed with a common absolutely continuous distribution function F. In this article, interest is in the problem of testing the null hypothesis that F belongs to some parametric family where the q‐dimensional parameter is unknown. We propose a general Chi‐squared test in which cell boundaries are data dependent. An estimator of the parameter obtained by minimizing a quadratic form resulting from a properly scaled vector of differences between Observed and Expected frequencies is used to construct the test. This estimator is known as the minimum chi‐square estimator. Large sample properties of the proposed test statistic are established using empirical processes tools. A simulation study is conducted to assess the performance of the test under parameter misspecification, and our procedures are applied to a fleet of Boeing 720 jet planes' air conditioning system failures.     

A Nonparametric Test Procedure Based on Quantiles for the Right Censored Data

In this study, we propose nonparametric tests using the several quantile statistics simultaneously for the right censored data. First of all, we consider statistics of the quadratic form with estimated covariance matrices. Then we derive the limiting distribution using the large sample approximation theory. Also we consider different forms of statistics such as the maximal and summing types with their limiting distributions. Then we illustrate our procedure with examples and compare performance among tests with empirical powers through a simulation study. Also we comment briefly on some interesting features including re-sampling methods as concluding remarks. Finally in Appendices, we provide proofs for the theoretic results needed for the derivation of the limiting distributions of the proposed test statistics.     

On Reading Test

There has been a long discussion over the construct validity of reading tests. In china's reading tests, multiple choice is the main test method in view of the4 long controversy over the validity of multiple choice, construct validation is called for to empirically test the hypothesized relationships between test scores and abilities. The national CET committee conducted a comprehensive validation study. As part of the project, the specialists studied the reading comprehension test' s validity by qualitative means, namely "introspective verbal reports". The analysis revealed that an overwhelming majority of the questions items were handled through "expected reading operations".     

中韩创新对出口贸易的影响比较——以专利为视点的实证研究

创新是知识经济时代的特征,是一国竞争力的主要源泉,专利授予量则是衡量一国创新状况的最好指标。在经济一体化的今天,一国的经济实力和该国的贸易状况有着密切的关系。通过EG协整检验、因果关系检验等方法,验证代表一国创新水平的专利尤其是发明专利对外贸出口的直接拉动效应。实证分析显示,在韩国,创新活动在增加出口方面扮演更重要的角色。这表明,一国竞争力的提高关键是自主创新能力的提升。     

当代大学生对女性印象内隐实验研究

本实验采用内隐联结测验（IAT）,回避社会赞许效应等干扰因素,考察了当代大学生对于女性印象的内隐态度,发现他们更认同与现代女性形象即他们女性印象是积极地,独立自主的。且这种内隐认同态度不存在性别差异、城乡差异及文理科差异。     

Support for a Fluid-Continuum Model of Sexual Orientation: A Large-Scale Internet Study

In a study with 17,785 subjects obtained over the Internet from the United States and 47 other countries, Kinsey's hypothesis that sexual orientation lies on a continuum was supported. Self-identifications of subjects as gay, straight, bisexual, and other corresponded to broad, skewed distributions, suggesting that such terms are misleading for many people. Sexual orientation range—roughly, how much flexibility someone has in expressing sexual orientation—was also measured. The results support a fluid-continuum model of sexual orientation, according to which genetic and environmental factors determine both the size of the sexual orientation range and the point at which an individual's sexual orientation is centered on the continuum.     

An update on ‘a comparative study of tests for homogeneity of variance’

Tests for equality of variances using independent samples are widely used in data analysis. Conover et al. [A comparative study of tests for homogeneity of variance, with applications to the outer continental shelf bidding data. Technometrics. 1981;23:351–361], won the Youden Prize by comparing 56 variations of popular tests for variance on the basis of robustness and power in 60 different scenarios. None of the tests they compared were robust and powerful for the skewed distributions they considered. This study looks at 12 variations they did not consider, and shows that 10 are robust for the skewed distributions they considered plus the lognormal distribution, which they did not study. Three of these 12 have clearly superior power for skewed distributions, and are competitive in terms of robustness and power for all of the distributions considered. They are recommended for general use based on robustness, power, and ease of application.     

Optimal design of repetitive group sampling plans for Weibull and gamma distributions with applications and comparison to the Birnbaum–Saunders distribution

In this paper, we propose a multiple deferred state repetitive group sampling plan which is a new sampling plan developed by incorporating the features of both multiple deferred state sampling plan and repetitive group sampling plan, for assuring Weibull or gamma distributed mean life of the products. The quality of the product is represented by the ratio of true mean life and specified mean life of the products. Two points on the operating characteristic curve approach is used to determine the optimal parameters of the proposed plan. The plan parameters are determined by formulating an optimization problem for various combinations of producer's risk and consumer's risk for both distributions. The sensitivity analysis of the proposed plan is discussed. The implementation of the proposed plan is explained using real-life data and simulated data. The proposed plan under Weibull distribution is compared with the existing sampling plans. The average sample number (ASN) of the proposed plan and failure probability of the product are obtained under Weibull, gamma and Birnbaum–Saunders distributions for a specified value of shape parameter and compared with each other. In addition, a comparative study is made between the ASN of the proposed plan under Weibull and gamma distributions.     

On testing random effects in the nested-error regression model

We derive an exact F-test for random effects in the nested-error regression model. The derivation utilizes a matrix decomposition that offers a transformation of the response vector into two independent subvectors. When the random effects are absent, the test statistic reduces to a ratio of two independent residual sums of squares that are computed by fitting a regression model using each subvector. A small simulation study compares the power of the F-test with various recent tests and shows that the proposed test has a competitive performance under small as well as large number of clusters.     

A goodness of fit test for multilevel survival data

No satisfactory goodness of fit test is available for multilevel survival data which occur when survival data are clustered or hierarchical in nature. Hence the aim of this research is to develop a new goodness of fit test for multilevel survival data and to examine the properties of the newly developed test. Simulation studies were carried out to evaluate the type ? error and the power. The results showed that the type I error holds for every combination tested and that the test is powerful against the alternative hypothesis of nonproportional hazards for all combinations tested.