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汇总数据、生态回归与投票转移AI 解读

Voting data typically comprise the marginal distributions of votes cast at two successive elections. The fact that these obtain separately for many voting precincts or areas enables one to estimate the actual transition probabilities for movements between the options available to the voter at each election. An aggregated compound multinomial model is proposed. This allows log-linear dependence on various covariates and specifies a simple and illuminating structure of random…

非对称损失函数下的贝叶斯估计与预测AI 解读

Estimators and predictors that are optimal relative to Varian's asymmetric LINEX loss function are derived for a number of well-known models. Their risk functions and Bayes risks are derived and compared with those of usual estimators and predictors. It is shown that some usual estimators, for example, a scalar sample mean or a scalar least squares regression coefficient estimator, are inadmissible relative to asymmetric LINEX loss by providing alternative estimators that…

极小极大收缩估计量的组合AI 解读

When one estimates a multivariate normal mean, the use of Stein estimation entails both the grouping of coordinates and the selection of a set of targets toward which to shrink each group. In this article we propose new minimax multiple shrinkage estimators that allow for multiple specifications of these aspects. We provide examples that are evaluated on real and simulated data, including an estimator that adaptively resolves the issue of combining possibly related…

采用多重计数规则调查稀有人群时的报告偏差与抽样误差AI 解读

This article examines a methodology to improve the efficiency of surveys to locate and estimate characteristics of rare populations. Two multiplicity counting rules are compared with a conventional rule in terms of reporting errors, sample variances, and survey yields. The analysis is based on data from two survey field experiments with diagnosed cancer patients and a subsample of their siblings or children who reside outside their households. The article concludes with a…

敏感主题调查中的回答偏差与可靠性AI 解读

Estimates of survey response bias and reliability are presented for six topics: receipt of welfare, income, alcohol use, drug use, criminal history, and embarrassing medical conditions. The estimates are derived from published full-design criterion validity studies. The common assumption that these characteristics are underreported is, in part, based on partial validity studies; the bias in estimating response parameters using partial designs is demonstrated. Evidence from…

用潜在马尔可夫模型估计多期面板中的回答误差AI 解读

When direct measures of response error are not available in multiwave panel data, latent Markov chain models can provide a useful framework for analysis of response errors. These models permit the estimation of real change and response error even when the observations are widely spaced. This methodology is illustrated with Social Security Administration panel data from the years 1971, 1972, and 1974 (see Frohlich 1975 and Social Security Administration 1979a,b) on…

两个来源均有聚类观测时的捕获—再捕获模型AI 解读

Capture—recapture models assume that individuals in the population are captured one at a time and independently of each other. There are often situations, however, where individuals are captured in small clusters or groups. This article provides a model that allows individuals to be captured in groups; the EM algorithm is used to estimate parameters in the model that include capture probabilities and the size of the population under study.

死因数据不完整时动物实验患病率与死亡率的非参数估计AI 解读

Age-specific prevalence and mortality estimators are important descriptors of disease development and the subsequent effects of a disease on longevity. Nonparametric maximum likelihood estimators for the prevalence and mortality functions are available for the case in which incidental and fatal occurrences of a disease can always be distinguished. This article generalizes these methods to allow the role of a disease in causing death to be uncertain for a subset of the…

扩展贝塔二项分布的二元回归及协变量测量误差诱发的相关性AI 解读

The beta-binomial distribution is extended to allow negative correlations among binary variates within an experimental unit. Regression models are proposed for both the binary variate response rate and for the pairwise correlation between binary variates, and corresponding likelihood estimation procedures are described. Binary regression problems are also considered, in which measurement errors in the regression variables represent the sole source of overdispersion. Some…

马来西亚儿童健康、母乳喂养与存活：随机效应Logit方法AI 解读

This study examines the possibility that estimation of the effect of breast-feeding on infant survival is affected by selection bias, in that children who are healthier at birth may be more likely to be breast-fed. Data are from the 1976 Malaysian Family Life Survey. "Ordinary logit models for breast-feeding and survival are estimated, and the results suggest that selection is indeed present. For example, children of higher birth weight appear to be more likely to be…

单侧二项检验的合并AI 解读

Six methods of combining k independent binomial test statistics are compared with respect to their median significance levels, asymptotic relative efficiencies, and accuracy of null distribution approximations. The test statistics considered are the minimum significance level, Fisher's omnibus test, the likelihood ratio, an approximate likelihood ratio, the Mantel-Haenszel statistic, and the sum of chis. Fisher's test and the likelihood ratio perform relatively well for all…

协方差分析中有序备择的并交秩检验AI 解读

For an analysis of covariance model (pertaining to completely randomized as well as complete block designs) based on the union-intersection principle, a general class of permutationally distribution-free rank tests for the ordered alternative problem is considered. The theory is supplemented by numerical studies.

关于平滑先验与非线性回归的一个注记AI 解读

A generalization of a nonparametric estimator proposed by Shiller (1984) is considered. The estimator is shown to be directly related to penalized least squares estimation and spline smoothing. Some simplifications concerning the computation of Shiller's estimator and corresponding posterior covariances are indicated.

最小二乘回归中缺失数据的诊断图AI 解读

The usual approach to handling missing data in a regression is to assume that the points are missing at random (MAR) and use either a fill-in method to replace the missing points or a method using maximally available pairs in the sample covariance matrix. We derive limits for the values of the least squares estimates of the coefficients (and their associated t statistics) when there are missing observations in one carrier. These limits are derived subject to a constraint on…

稀疏列联表中对数线性模型的拟合优度检验AI 解读

The asymptotic normality of the likelihood ratio goodness-of-fit statistic is demonstrated for testing the fit of log-linear models with closed form maximum likelihood estimates in sparse contingency tables. Unlike the traditional chi-squared theory, the number of categories in the table increases as the sample size increases, but not all of the expected frequencies are required to become large. Some results of a small Monte Carlo study are presented. The traditional…

预测规则的表观错误率有多大偏差？AI 解读

A regression model is fitted to an observed set of data. How accurate is the model for predicting future observations? The apparent error rate tends to underestimate the true error rate because the data have been used twice, both to fit the model and to check its accuracy. We provide simple estimates for the downward bias of the apparent error rate. The theory applies to general exponential family linear models and general measures of prediction error. Special attention is…

可忽略无响应下简单随机样本的多重插补区间估计AI 解读

Several multiple imputation techniques are described for simple random samples with ignorable nonresponse on a scalar outcome variable. The methods are compared using both analytic and Monte Carlo results concerning coverages of the resulting intervals for the population mean. Using m = 2 imputations per missing value gives accurate coverages in common cases and is clearly superior to single imputation (m = 1) in all cases. The performances of the methods for various m can…

天气与售电量关系的半参数估计AI 解读

A nonlinear relationship between electricity sales and temperature is estimated using a semiparametric regression procedure that easily allows linear transformations of the data. This accommodates introduction of covariates, timing adjustments due to the actual billing schedules, and serial correlation. The procedure is an extension of smoothing splines with the smoothness parameter estimated from minimization of the generalized cross-validation criterion introduced by…

住房单元人口估计法的回顾与评估AI 解读

"The housing unit (HU) method is used by public and private agencies throughout the United States to make local population estimates. This article describes many of the different types of data and techniques that can be used in applying the HU method, and it discusses the strengths and weaknesses of each. Empirical evidence from four different states is provided, comparing the accuracy of HU population estimates with the accuracy of other commonly used estimation techniques.…

概率论及其应用AI 解读

Foundations.- Background Material and Preliminaries.- Independence and Strong Convergence.- Conditioning and Some Dependence Classes.- Analytical Theory.- Probability Distributions and Characteristic Functions.- Weak Limit Laws.- Applications.- Stopping Times, Martingales, and Convergence.- Limit Laws for Some Dependent Sequences.- A Glimpse of Stochastic Processes.

摘要暂缺

药学统计：实践与临床应用AI 解读

Basic definitions and concepts data graphics introduction to probability - the binomial and normal probability distributions choosing samples statistical inference - estimation and hypothesis testing sample size and power linear regression andcorrelation analysis of variance factorial designs transformations and outliers experimental design in clinical trials quality control validation computer-intensive methods nonparametric methods optimization techniques and screening…

摘要暂缺

两阶段抽样中子样本规模的选择AI 解读

This article presents a simple method for choosing the subsample size m in two-stage sampling when the values of the relevant design parameters, the variance ratio and the cost ratio, are not known exactly but can only be assumed to lie within some specific range. Measuring the efficiency of a choice of m by its precision relative to the optimum choice, which depends on the parameters, it is proposed to choose m so that its minimum efficiency, over the specified range of…