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健康研究中的统计推断问题：以吸烟与肺癌争议为例AI 解读

Disagreement about the role of cigarette smoking in lung cancer is traced to three sources of confusion. In the first, there is lack of agreement as to the definition of terms and what is implied when a specific factor is said to be a cause of a particular disease. A suggested definition is offered to clarify one of the issues causing dissent. The second area of disagreement concerns the method of measuring the strength of the relationship in a 2 × 2 table, and whether the…

健康领域的统计推断问题：以吸烟与肺癌争论为例AI 解读

Disagreement about the role of cigarette smoking in lung cancer is traced to three sources of confusion. In the first, there is lack of agreement as to the definition of terms and what is implied when a specific factor is said to be a cause of a particular disease. A suggested definition is offered to clarify one of the issues causing dissent. The second area of disagreement concerns the method of measuring the strength of the relationship in a 2 × 2 table, and whether the…

普通最小二乘与两阶段最小二乘估计量的精确抽样分布AI 解读

This paper presents the exact sampling distributions of the ordinary and the two-stage least squares estimators of a structural parameter in a structural equation with two endogenous variables in a complete system of stochastic equations. The results show that the distributions of the two estimators are essentially similar to each other. It can also be seen that both distributions depend crucially upon the deviation of a regression coefficient of disturbance terms of two…

There occurs on some occasions a difficulty in deciding the direction of causality between two related variables and also whether or not feedback is occurring. Testable definitions of causality and feedback are proposed and illustrated by use of simple two-variable models. The important problem of apparent instantaneous causality is discussed and it is suggested that the problem often arises due to slowness in recording information or because a sufficiently wide class of…

We begin by considering a simple model of accumulation, with a linear savings function, a constant reproduction rate, homogeneous labor, and equal division of wealth among one's heirs. In such an economy, if the balanced growth path is stable, all wealth and income is asymptotically evenly distributed, with the possible exception, in the case of negative savings at zero income, of a group with zero wealth. In the process of accumulation, there may, however, be a period…

完全随机布局下裂区试验统计分析的若干方面AI 解读

The statistical analysis of completely randomized “split-plot” experiments is discussed from the point of view of the underlying multivariate model. In doing this, first certain well-known aspects of the parametric case are reviewed; however, attention is primarily directed toward the development of appropriate non-parametric procedures. The general structure of “split-plot” experiments involves N randomly chosen subjects to whom treatments have been assigned according to a…

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多元成对比较：单变量模型的推广及估计与检验AI 解读

This study is concerned with the development of an extension of the Bradley-Terry model for paired comparisons to situations in which responses to paired comparisons are obtained on each of several characteristics. At the outset a probability model for multivariate paired comparisons is proposed that may be represented in several distinct ways. An iterative procedure for obtaining maximum-likelihood estimates of the parameters introduced into the model is given and its…

将残差用作伴随协变量AI 解读

Suppose that there is correlation between the yields of successive or adjacent experimental units. An estimator of treatment effects using the residuals of adjacent plots as a concomitant variable is investigated. It is shown to be very close to the maximum likelihood estimator when the errors form a first-order autoregressive series.

利用随机分配控制选择偏差AI 解读

In comparing two treatments, suppose the suitable subjects arrive sequentially and must be treated at once. In such situations, if the experiment calls for fixed treatment numbers, the experimenter can, using his knowledge of the number of treatments that have been assigned, bias the experiment by his selection of subjects. If we consider the method of assigning treatments as an experimental design, Blackwell & Hodges (1957) have shown that the minimax design is the…

通过线性规划求配对比较的最大似然排序AI 解读

The problem of ranking n objects from ‘best’ to ‘worst’, using the results of a paired comparison experiment, is formulated as a linear programming problem with the logarithm of the likelihood as the objective function. The constraints are determined by the transitivity relationships implied in a ranking. The linear program will determine maximum likelihood rankings for the k fold replicated paired comparison experiment with or without the possibility of ties. The method is…

将残差用作伴随变量AI 解读

Suppose that there is correlation between the yields of successive or adjacent experimental units. An estimator of treatment effects using the residuals of adjacent plots as a concomitant variable is investigated. It is shown to be very close to the maximum likelihood estimator when the errors form a first-order autoregressive series.

The power curves of three two-sample tests are compared in small samples from the exponential and four forms of the Weibull distribution with and without censoring. The tests considered are: F ratio, modified F ratio (F′ test), and a generalized Wilcoxon test (W test). Monte Carlo methods are used to obtain power curves for each test with sample sizes 20 and 50. The F test is known to be most efficient when sampling is from exponential distributions. If sampling is from…

多变量成对比较：单变量模型的扩展及估计与检验AI 解读

This study is concerned with the development of an extension of the Bradley-Terry model for paired comparisons to situations in which responses to paired comparisons are obtained on each of several characteristics. At the outset a probability model for multivariate paired comparisons is proposed that may be represented in several distinct ways. An iterative procedure for obtaining maximum-likelihood estimates of the parameters introduced into the model is given and its…

规模显著变化时按规模概率区域样本的重新设计AI 解读

For purposes of obtaining statistical data by enumeration, systematic sampling with probability proportional to size in one or more stages is frequently employed. The article describes two methods of changing the measures of sizes without introducing a bias in the estimation procedure. They result in the reduction of the variance of sample take, and, in the illustrative material presented, result in varying degrees of overlap before and after the changes of sizes. These…

结构系数估计量的精确分布AI 解读

The distribution studied is that of an estimator of a structural parameter appearing in a system of linear simultaneous equations. The relationship between the bias and the true parameter value is analysed and the bias is tabulated for selected values of the parameters of the distribution. It is also shown that the estimator possesses finite moments up to order v where v is the number of overidentifying restrictions and that the estimator converges to the true parameter…

摘要暂缺

U NTIL the mid-1950's, the traditional view on the consumption of housing had been that the elasticity of housing consumption with respect to current income was less than unity.' However, recent literature on the theory of consumption function [15] [4] has pointed out that, in relating income to consumption, the concept of income should be that of permanent income rather than current or measured income, and that the use of measured income imparts a downward bias in…

样本分位数渐近分布的一则说明AI 解读

Summary This paper gives a rigorous proof, under conditions believed to be minimal, of the asymptotic normality of a finite set of quantiles of a random sample from an absolutely continuous distribution. The proof is substantially simpler than those that have previously been published.

用于因果分析与规划的新型收入不平等度量AI 解读

A new system of inequality indicators is introduced in the paper. It has been elaborated for measuring income inequalities, but can serve as inequality measures for other phenomena as well. The new indicators not only measure the degree of the inequality but are also suitable for measuring its economic motivation. Properties of the new measures, including large sample properties of their estimators, are discussed. The case of the lognormal distribution is of special…

近似设定与 k 类估计量的选择AI 解读

This paper carries on work in [2] and [4] on the asymptotic effects of small specification error in simultaneous equation estimation. The specification errors considered are inherent in the approximate nature of econometric models. It is shown that for any parameter and small enough specification error, the probability limits of two-stage least squares and limited-information maximum-likelihood, while different, lie on the same side of the true parameter value, the…

正态性假设下虚拟变量回归的渐近方差AI 解读

Asymptotic variances are derived for estimators of the dummy variate regression model described in [6]. The results are summarized by asymptotic covariance matrices for the regression coefficients, the estimated logarithms of odds given X, and the estimated probabilities given X. A two population two variable example illustrates the results.

正态假设下虚拟变量回归的渐近方差AI 解读

Asymptotic variances are derived for estimators of the dummy variate regression model described in [6]. The results are summarized by asymptotic covariance matrices for the regression coefficients, the estimated logarithms of odds given X, and the estimated probabilities given X. A two population two variable example illustrates the results.