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超总体模型下调查加权推断的等效样本量与等效自由度修正AI 解读

A number of procedures have been proposed to attack different inference problems for data drawn from a survey with a complex sample design (i.e., a design that entails unequal weighting). Most procedures either are based on finite-population assumptions or require the specification of an explicit model using a superpopulation rationale. Herein we propose some relatively simple approximate procedures that are based on a superpopulation model. They provide valid variance…

基于 DNA 指纹的法医推断AI 解读

The recent discovery of hypervariable regions of the human genome provides scientists with an important new tool for forensic inference. The DNA data obtained from these hypervariable regions have been dubbed DNA fingerprints. Despite the potential power of DNA fingerprints, their use has been fraught with controversy, deriving in part from a lack of statistical methods to summarize the information contained in a DNA fingerprint. This article provides such a method, useful…

预测工作记忆失误：主观贝叶斯模型选择方法AI 解读

We use Bayes factors to compare two alternative characterizations of human working memory load in their ability to predict errors in database query-writing tasks. The first measures working memory load by the number of different features each task contains, while the second attempts instead to measure the complexity of the task by giving more weight to features that require more mental time for their correct execution. We reanalyze data from a previously conducted experiment…

结合永久存续比例回归的加速失效时间模型：日本终身雇佣分析AI 解读

Accelerated failure-time regression models with an additional regression model for the surviving fraction are proposed for the analysis of events that may never occur, regardless of censoring, for some people in the population risk set. The models attempt to estimate simultaneously the effects of covariates on the acceleration/deceleration of the timing of a given event and the surviving fraction; that is, the proportion of the population for which the event never occurs.…

肿瘤生长的空间统计分析AI 解读

Growth models for tumors commonly are developed for a one-dimensional summary (e.g., number of cells, volume). At the supracellular level, however, ignoring tumor shape leads to oversimplification of the growth mechanism. For example, an oncologist would view the discovery of a compact tumor of volume v differently from the discovery of two osculatory compact tumors each of volume v/2. This article presents a growth model that uses shape information at a previous time to…

偏秩相关的置信区间AI 解读

A partial rank correlation coefficient T(n) XY|Z , based on comparing pairs for which the values of the conditioning variable follow each other in a numerical ordering, is studied. Simulation results show that it is possible to obtain reasonably good confidence intervals by estimating σ 2/(1 − τ 2 XY|Z ). The advantage of using the coefficient T(n) XY|Z is that it is always clear what this coefficient measures, in contrast to, for example, Pearson's, Spearman's, or Kendall's…

利用 Gibbs 采样分析参数约束与截断数据问题AI 解读

Constrained parameter problems arise in a wide variety of applications, including bioassay, actuarial graduation, ordinal categorical data, response surfaces, reliability development testing, and variance component models. Truncated data problems arise naturally in survival and failure time studies, ordinal data models, and categorical data studies aimed at uncovering underlying continuous distributions. In many applications both parameter constraints and data truncation are…

期望界限的计算AI 解读

One method for evaluating the sensitivity of a Bayesian analysis is to embed the prior into a class of priors. Then bounds on prior and posterior quantities of interest must be computed. This approach to inference, often called robust Bayesian inference, has received much attention lately. Implementing robust Bayesian methods entails difficult computations, especially if the parameter space is high dimensional. In this article we develop a Monte Carlo approach to computing…

多类别响应数据的精确分布计算AI 解读

This article presents an efficient method for computing exact conditional distributions of the sufficient statistics for the parameters of four polytomous response models. For nominal response, two baseline category logit models and, for ordinal response, two adjacent categories logit models are considered. The method consists of recursive generation of the joint distribution of the sufficient statistics, augmented by a technique to slice off portions of the evolving sample…

精确拟合优度检验的方法AI 解读

Numerous goodness-of-fit tests with asymptotic chi-squared distributions have been proposed for discrete multivariate data, and there has been much discussion about using asymptotic results for computing critical values when there are small expected cell values. Although exact methods would be preferred in these situations, it generally is believed that such methods are computationally intractable. We propose methods for calculating exact distributions and significance…

泊松与二项回归模型的过度离散检验AI 解读

In this article a method for obtaining tests for overdispersion with respect to a natural exponential family is derived. The tests are designed to be powerful against arbitrary alternative mixture models where only the first two moments of the mixed distribution are specified. Various tests for extra-Poisson and extra-binomial variation are obtained as special cases; the use of a particular test may be motivated by a consideration of the mechanism through which the…

线性回归中的一步 GM 估计与推断稳定性AI 解读

The folklore on one-step estimation is that it inherits the breakdown point of the preliminary estimator and yet has the same large sample distribution as the fully iterated version as long as the preliminary estimate converges faster than n –1/4, where n is the sample size. We investigate the extent to which this folklore is valid for one-step GM estimators and their associated standard errors in linear regression. We find that one-step GM estimates based on Newton-Raphson…

边界估计AI 解读

A data set consists of independent observations taken at the nodes of a grid. An unknown boundary partitions the grid into two regions. All the observations coming from a particular region share a common distribution, but the distributions are different for the two different regions. These two distributions are entirely unknown and need not differ in their means, medians, or any other measure of “level.” The grid is of arbitrary dimension, and its mesh is rectangular. Our…

协方差矩阵同质性检验的自助法临界值AI 解读

Bartlett's modified likelihood ratio statistic A is often suggested in multivariate analysis for testing equality of covariance matrices. Unfortunately, the χ 2-approximation to the null distribution of −2 log Λ is useful only when the data is normally distributed. This article presents a pooled bootstrap procedure that replaces the χ 2-approximation and makes Bartlett's statistic a useful tool for data analysis. This procedure also applies to most quadratic form test…

调查抽样中的校准估计量AI 解读

This article investigates estimation of finite population totals in the presence of univariate or multivariate auxiliary information. Estimation is equivalent to attaching weights to the survey data. We focus attention on the several weighting systems that can be associated with a given amount of auxiliary information and derive a weighting system with the aid of a distance measure and a set of calibration equations. We briefly mention an application to the case in which the…

基于伴侣研究数据的 HIV 传染性时间变化分析AI 解读

Statistical analyses of data from studies of human immunodeficiency virus (HIV) transmission in partners of infected individuals often focus on estimation of the per contact probability of virus transmission, or infectivity. Of particular interest is evaluating whether the infectivity changes during the course of a partnership and identifying factors that influence the infectiousness of the initially infected partner (called the index case) and the susceptibility of the…

测量误差问题：原子弹幸存者辐射剂量反应分析的启示AI 解读

Some basic issues in the errors-in-variables problem are discussed, in terms of considerations that arose in analyses of radiation effects on atomic bomb survivors. The setting essentially involves generalized linear models for the response variables, a very nonnormal distribution of the true covariable, and multiplicative errors in the observed covariable. Consideration is given to distinctions between structural and functional modeling. It is argued that careful attention…

入学年龄对教育程度的影响：结合两样本矩的工具变量应用AI 解读

We present a model in which compulsory school attendance laws, which typically require school attendance until a specified birthday, induce a relationship between years of schooling and age at school entry. Variation in school starting age created by children's dates of birth provides a natural experiment for estimating the effect of age at school entry. Because no large data set contains information on both age at school entry and educational attainment, we use an…

摘要暂缺

行为研究中的统计模型AI 解读

Contents: Introduction. Statistics, Probability, and Decision. Basic Concepts. Contrasts on Means. Testing a Statistical Hypothesis. Simple Analysis of Variance. Regression and ANOVA in the Linear Model Framework. Two-Way Factorial Designs. Repeated-Measures Designs. Unbalanced Designs and Nonorthogonality.

非线性多元分析AI 解读

Conventions and Controversies in Multivariate Analysis. Coding of Categorical Data. Homogeneity Analysis. Nonlinear Principal Components Analysis. Nonlinear Generalized Canonical Analysis. Nonlinear Canonical Correlation Analysis. Asymmetric Treatment of Sets: Some Special Cases, Some Future Programs. Multidimensional Scaling and Correspondence Analysis. Models as Gauges for the Analysis of Binary Data. Reflections on Restrictions. Nonlinear Multivariate Analysis: Principles…

生物学中的随机化与蒙特卡洛方法AI 解读

Part 1 Randomization tests and confidence intervals: the idea of a randomization test examples of a randomization test aspects of randomization testing raised by the examples confidence intervals from randomization. Part 2 Monte Carlo and other computer intensive methods: Monte Carlo tests jackknifing bootstrapping bootstrap tests of significance and confidence intervals. Part 3 Some general considerations: power determining how many randomizations are needed determining a…

偏秩相关系数的置信区间AI 解读

A partial rank correlation coefficient T(n) XY|Z , based on comparing pairs for which the values of the conditioning variable follow each other in a numerical ordering, is studied. Simulation results show that it is possible to obtain reasonably good confidence intervals by estimating σ 2/(1 − τ 2 XY|Z ). The advantage of using the coefficient T(n) XY|Z is that it is always clear what this coefficient measures, in contrast to, for example, Pearson's, Spearman's, or Kendall's…

摘要暂缺