Letters to the Editor

Letters to the Editor will be confined to discussions of papers which have appeared in The American Statistician and of important issues facing the statistical community. Letters discussing papers in The American Statistician must be received within two months of publication of the paper; the author of the paper will then be given an opportunity to reply and the letters and reply will be published together. All letters to the Editor will be refereed. Corrections of errors which have been noted in papers published in The American Statistician will be listed in Corrigenda at the end of this section.     

Letters to the Editor

Letters to the editor will be confined to discussions of papers that have appeared in The American Statistician and to important issues facing the statistical community. Letters discussing papers in The American Statistician must be received within two months of publication of the paper; the author of the paper will then be given an opportunity to reply, and the letters and reply will be published together. All letters to the editor will be refereed. Corrections of errors that have been noted in papers published in The American Statistician will be listed as corrections at the end of this section.     

Letters to the Editor

Letters to the editor will be confined to discussions of papers that have appeared in The American Statistician and of important issues facing the statistical community. Letters discussing papers in The American Statistician must be received within two months of publication of the paper; the author of the paper will then be given an opportunity to reply, and the letters and reply will be published together. All letters to the editor will be refereed. Corrections of errors that have been noted in papers published in The American Statistician will be listed as corrections at the end of this section.     

Referees' Services 1980

Papers submitted to The Australian Journal of Statistics have been refereed during 1980 by the persons named below. The Editor thanks the referees for their generous help.     

The Religion of Statistics as Practiced in Medical Journals

Commentaries are informative essays dealing with viewpoints of statistical practice, statistical education, and other topics considered to be of general interest to the broad readership of The American Statistician. Commentaries are similar in spirit to Letters to the Editor, but they involve longer discussions of background, issues, and perspectives. All commentaries will be refereed for their merit and compatibility with these criteria.

The way in which hypothesis tests are often used as the sole tool of statistics in medical research is satirized. This is followed by a suggestion for reform.     

Papers That Evaluate Computer Programs

Commentaries are informative essays dealing with viewpoints of statistical practice, statistical education, and other topics considered to be of general interest to the broad readership of The American Statistician. Commentaries are similar in spirit to Letters to the Editor, but they involve longer discussions of background, issues, and perspectives. All commentaries will be refereed for their merit and compatibility with these criteria.     

Encoding dissimilarity data for statistical model building

We summarize, review and comment upon three papers which discuss the use of discrete, noisy, incomplete, scattered pairwise dissimilarity data in statistical model building. Convex cone optimization codes are used to embed the objects into a Euclidean space which respects the dissimilarity information while controlling the dimension of the space. A “newbie” algorithm is provided for embedding new objects into this space. This allows the dissimilarity information to be incorporated into a smoothing spline ANOVA penalized likelihood model, a support vector machine, or any model that will admit reproducing kernel Hilbert space components, for nonparametric regression, supervised learning, or semisupervised learning. Future work and open questions are discussed. The papers are:     

Capture-recapture: Before and after EURING 2000

Capture-recapture studies and analyses have become an important tool for the study of bird populations. One reason for the rapid advancement in this area has been the EURING conferences where population biologists and statisticians meet to review recent progress, identify areas that require further work, and work collaborately to solve real world problems. In this paper, we forecast the needs for future research in this area and review the recent conference to try and identify what questions are yet unsolved. This EURING conference was dedicated to Dr George Seber who was the author of a number of key papers and whose name is synonymous with 'The estimation of animal abundance and related parameter' (Seber, 1982). He has retired from working in this field.     

Capture-recapture: before and after EURING 2000

Capture-recapture studies and analyses have become an important tool for the study of bird populations. One reason for the rapid advancement in this area has been the EURING conferences where population biologists and statisticians meet to review recent progress, identify areas that require further work, and work collaborately to solve real world problems. In this paper, we forecast the needs for future research in this area and review the recent conference to try and identify what questions are yet unsolved. This EURING conference was dedicated to Dr George Seber who was the author of a number of key papers and whose name is synonymous with 'The estimation of animal abundance and related parameter' (Seber, 1982). He has retired from working in this field.     

Sample size determination in step-down and step-up multiple tests for comparing treatments with a control

We address the problem of sample size determination in multiple comparisons of k treatments with a control for step-down and step-up testing, assuming normal data and homogeneous variances. We define power as the probability of correctly rejecting all hypotheses for which the treatment vs. control difference exceeds a specified value. Our paper supplements papers by Hayter and Tamhane (J. Statist. Plann. Inference 27 (1991) 271–290) who solved the problem for one-sided comparisons using the step-down procedure and by Liu (J. Statist. Plann. Inference 62 (1997b) 255–261) who considered the two-sided case using the single-step method. We provide expressions that allow computer evaluation of the power and necessary sample sizes for one- and two-sided tests using either step-down or step-up procedures. Tables are given from which sample sizes to guarantee a specified power can be determined.     

协整理论在中国的应用情况研究

协整理论是20世纪80年代由格兰杰等人发展起来的计量经济学工具，但是2003年之前在中国学术界的应用并不广泛。自从格兰杰因首先创立协整理论而获得2003年诺贝尔经济学奖之后情况发生了根本性变化，大量介绍或应用协整理论的经济文献涌现出来，甚至到了泛滥的地步。以从《中国期刊网》上得到的资源为依托，对这一现状进行探索性地剖析，认为目前中国学术界对协整理论的应用既有合理的地方，也有盲目跟风甚至是相互矛盾的地方，总体上来说运用质量有待提高。     

Covariance Analysis for Split-Plot and Split-Block Designs

Commentaries are informative essays dealing with viewpoints of statistical practice, statistical education, and other topics considered to be of general interest to the broad readership of The American Statistician. Commentaries are similar in spirit to Letters to the Editor, but they involve longer discussions of background, issues, and perspectives. All commentaries will be refereed for their merit and compatibility with these criteria.

Proper methodology for the analysis of covariance for experiments designed in a split-plot or split-block design is not found in the statistical literature. Analyses for these designs are often performed incompletely or even incorrectly. This is especially true when popular statistical computer software packages are used for the analysis of these designs. This article provides several appropriate models, ANOVA tables, and standard errors for comparisons from experiments arranged in a standard split-plot, split–split-plot, or split-block design where a covariate has been measured on the smallest size experimental unit.     

Moments of the trace of a noncentral wishart matrix

Several articles have appeared on the moments of the trace of a noncentral Wishart matrix. Partial results are given in these papers but the representations of these partial results are often too cumbersome for any practical use. In this paper general results are given in compact form which are readily usable in practical problems.     

Lag Length Selection for Unit Root Tests in the Presence of Nonstationary Volatility

A number of recent papers have focused on the problem of testing for a unit root in the case where the driving shocks may be unconditionally heteroskedastic. These papers have, however, taken the lag length in the unit root test regression to be a deterministic function of the sample size, rather than data-determined, the latter being standard empirical practice. We investigate the finite sample impact of unconditional heteroskedasticity on conventional data-dependent lag selection methods in augmented Dickey–Fuller type regressions and propose new lag selection criteria which allow for unconditional heteroskedasticity. Standard lag selection methods are shown to have a tendency to over-fit the lag order under heteroskedasticity, resulting in significant power losses in the (wild bootstrap implementation of the) augmented Dickey–Fuller tests under the alternative. The proposed new lag selection criteria are shown to avoid this problem yet deliver unit root tests with almost identical finite sample properties as the corresponding tests based on conventional lag selection when the shocks are homoskedastic.     

The most-cited statistical papers

We attempt to identify the 25 most-cited statistical papers, providing some brief commentary on each paper on our list. This list consists, to a great extent, of papers that are on non-parametric methods, have applications in the life sciences, or deal with the multiple comparisons problem. We also list the most-cited papers published in 1993 or later. In contrast to the overall most-cited papers, these are predominately papers on Bayesian methods and wavelets. We briefly discuss some of the issues involved in the use of citation counts.     

基于加权网随机区块模型的学术热点提取算法

学术热点在把握科学前沿、掌握学术动向、制订科研规划、学术作品评审等领域中有广泛的应用。针对学术热点发现中对文献市场选择性影响体现不足和热点内容结构表现单一的问题,本文提出了以学者选读文献为基础的学术热点提取模型和算法,设计了基于加权网模块社群挖掘算法的随机区组模型两阶段算法,用于发现带结构的学术热点,模拟和实证研究均表明算法在学术热点提取中取得良好效果。     

The foundation of experimental design and observation

Summary Despite a very large literature on experimental design there are few papers which discuss the fundamentals, certainly compared to work on statistical inference. This paper tries to address some of the issues in a way which draws together some different fields such as search, group-testing and entropy based methods. An important philosophical distinction is between active and passive observation and examples introduce this subject. There are close connections with the approach tof Taguchi in engineering. This paper, the following discussion, the contribution of R. Fontana and the reply of H. P. Wynn are a result of the seminar hold in Rome, on the 6th October 1993. The Editorial Board wishes to thank Prof. Alessandra Giovagnoli for the organization of the meeting.     

Confidence intervals for survival quantiles in the Cox regression model

Median survival times and their associated confidence intervals are often used to summarize the survival outcome of a group of patients in clinical trials with failure-time endpoints. Although there is an extensive literature on this topic for the case in which the patients come from a homogeneous population, few papers have dealt with the case in which covariates are present as in the proportional hazards model. In this paper we propose a new approach to this problem and demonstrate its advantages over existing methods, not only for the proportional hazards model but also for the widely studied cases where covariates are absent and where there is no censoring. As an illustration, we apply it to the Stanford Heart Transplant data. Asymptotic theory and simulation studies show that the proposed method indeed yields confidence intervals and bands with accurate coverage errors.     

关于单变量统计过程控制图某些研究结果简介

文章仅对一元连续变量的静态与动态控制图研究现状进行了简单的总结和介绍,并给出了较详细的参考文献,希望为国内开展此方向的研究抛砖引玉。     

Applying the GLM Variance Assumption to Overcome the Scale-Dependence of the Negative Binomial QGPML Estimator

Recently, various studies have used the Poisson Pseudo-Maximal Likehood (PML) to estimate gravity specifications of trade flows and non-count data models more generally. Some papers also report results based on the Negative Binomial Quasi-Generalised Pseudo-Maximum Likelihood (NB QGPML) estimator, which encompasses the Poisson assumption as a special case. This note shows that the NB QGPML estimators that have been used so far are unappealing when applied to a continuous dependent variable which unit choice is arbitrary, because estimates artificially depend on that choice. A new NB QGPML estimator is introduced to overcome this shortcoming.