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Estimation of gillnet and hook selectivity using log-linear models

ICES JOURNAL OF MARINE SCIENCE 1997年第3期54卷 471-477页

作者： Millar, RB Holst, R UNIV OTAGO DEPT MATH & STATDUNEDINNEW ZEALAND CONSTAT N SEA CTRDK-9850 HIRTSHALSDENMARK

The log-linear modelling capabilities of existing statistical software permit a generalization of Holt's indirect estimation method by allowing several different selection curve models to be fitted to catch data from an arbitrary number of mesh sizes. This also facilitates the use of formal inferential procedures such as model selection, assessment of relative fishing powers, estimation of standard errors, and permits inclusion of knowledge regarding the shape of the population length distribution. This methodology is equally applicable to estimation of hook selectivity. (C) 1997 International Council for the Exploration of the Sea.

关键词： count data gillnet selectivity hook selectivity log-linear models selection curves SELECT method maximum likelihood

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Automatic aggregation of categories in multivariate contingency tables using information theory

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COMPUTATIONAL STATISTICS & DATA ANALYSIS 1999年第3期29卷 285-294页

作者： Ocerin, JMC Mohedano, RE Segador, AG Univ Cordoba E-14080 Cordoba Spain

Low expected frequencies in tests associated to log-linear models building are treated with the aim df providing a methodology, useful for nonstatistician users, to analyse multivariate contingency tables. A procedure that reproduces the decisions of a statistical analyst studying a multivariate contingency table and confronted with low expected frequencies is provided, using the Bayesian information criterion to select a variable over which the aggregation should be done, and the entropy of Shannon to decide which categories should be aggregated. Prior opinions and knowledge about the feasibility of aggregation of categories within the context where the data have been collected are included in the system. The procedure has some user friendly techniques oriented to nonstatisticians, and it allowed greater efficiency when there are several multivariate tables to be analysed using some variables that can be included in different log-linear models. (C) 1999 Elsevier Science B.V. All rights reserved.

关键词： collapsibility multivariate categorical data analysis contingency tables log-linear models information theory information criterion

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Classical multilevel and Bayesian approaches to population size estimation using multiple lists

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JOURNAL OF THE ROYAL STATISTICAL SOCIETY SERIES A-STATISTICS IN SOCIETY 1999年第3期162卷 383-405页

作者： Fienberg, SE Johnson, MS Junker, BW Carnegie Mellon Univ Dept Stat Pittsburgh PA 15213 USA

One of the major objections to the standard multiple-recapture approach to population estimation is the assumption of homogeneity of individual 'capture' probabilities. Modelling individual capture heterogeneity is complicated by the fact that it shows up as a restricted form of interaction among lists in the contingency table cross-classifying list memberships for all individuals. Traditional log-linear modelling approaches to capture-recapture problems are well suited to modelling interactions among lists but ignore the special dependence structure that individual heterogeneity induces. A random-effects approach, based on the Rasch model from educational testing and introduced in this context by Darroch and co-workers and Agresti, provides one way to introduce the dependence resulting from heterogeneity into the log-linear model;however, previous efforts to combine the Rasch-like heterogeneity terms additively with the usual log-linear interaction terms suggest that a more flexible approach is required. In this paper we consider both classical multilevel approaches and fully Bayesian hierarchical approaches to modelling individual heterogeneity and list interactions. Our framework encompasses both the traditional log-linear approach and Various elements from the full Rasch model. We compare these approaches on two examples, the first arising from an epidemiological study of a population of diabetics in Italy, and the second a study intended to assess the 'size' of the World Wide Web. We also explore extensions allowing for interactions between the Rasch and log-linear portions of the models in both the classical and the Bayesian contexts.

关键词： log-linear models Markov chain Monte Carlo methods multiple-recapture census quasi-symmetry Rasch model

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Beyond kappa: A review of interrater agreement measures

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CANADIAN JOURNAL OF STATISTICS-REVUE CANADIENNE DE STATISTIQUE 1999年第1期27卷 3-23页

作者： Banerjee, M Wayne State Univ Sch Med Ctr Healthcare Effectiveness Res Detroit MI 48201 USA Univ New Hampshire Dept Math Durham NH 03824 USA

In 1960, Cohen introduced the kappa coefficient to measure chance-corrected nominal scale agreement between two raters. Since then, numerous extensions and generalizations of this inter-rater agreement measure have been proposed in the literature. This paper reviews and critiques various approaches to the study of interrater agreement, for which the relevant data comprise either nominal or ordinal categorical ratings from multiple raters. It presents a comprehensive compilation of the main statistical approaches to this problem, descriptions and characterizations of the underlying models, and discussions of related statistical methodologies for estimation and confidence-interval construction. The emphasis is on various practical scenarios and designs that underlie the development of these measures, and the interrelationships between them.

关键词： kappa coefficient intraclass correlation log-linear models nominal data ordinal data

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Extending mosaic displays: Marginal, conditional, and partial views of categorical data

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JOURNAL OF COMPUTATIONAL AND GRAPHICAL STATISTICS 1999年第3期8卷 373-395页

作者： Friendly, M York Univ Dept Psychol N York ON M3J 1P3 Canada

This article first illustrates the use of mosaic displays for the analysis of multiway contingency tables. We then introduce several extensions of mosaic displays designed to integrate graphical methods for categorical data with those used for quantitative data. The scatterplot matrix shows all pairwise (bivariate marginal) views of a set of variables in a coherent display. One analog for categorical data is a matrix of mosaic displays showing some aspect of the bivariate relation between all pairs of variables. The simplest case shows the bivariate marginal relation for each pair of variables. Another case shows the conditional relation between each pair, with all other variables partialled out. For quantitative data this represents (a) a visualization of the conditional independence relations studied by graphical models, and (b) a generalization of partial residual plots. The conditioning plot, or coplot, shows a collection of partial views of several quantitative variables, conditioned by the values of one or more other variables. A direct analog of the coplot for categorical data is an array of mosaic plots of the dependence among two or more variables, stratified by the values of one or more given variables. Each such panel then shows the partial associations among the foreground variables;the collection of such plots shows how these associations change as the given variables vary.

关键词： categorical data conditional independence coplots correspondence analysis graphical models log-linear models mosaic matrix scatterplot matrix

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Capture-recapture models including covariate effects

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AMERICAN JOURNAL OF EPIDEMIOlogY 1999年第4期149卷 392-400页

作者： Tilling, K Sterne, JAC Guys Kings & St Thomass Sch Med Dept Publ Hlth Sci London SE1 3QD England

Capture-recapture methods are used to estimate the incidence of a disease, using a multiple-source registry. Usually, log-linear methods are used to estimate population size, assuming that not all sources of notification are dependent. Where there are categorical covariates, a stratified analysis can be performed. The multinomial legit model has occasionally been used. In this paper, the authors compare log-linear and legit models with and without covariates, and use simulated data to compare estimates from different models. The crude estimate of population size is biased when the sources are not independent. Analyses adjusting for covariates produce less biased estimates. In the absence of covariates, or where all covariates are categorical, the log-linear model and the legit model are equivalent. The log-linear model cannot include continuous variables. To minimize potential bias in estimating incidence, covariates should be included in the design and analysis of multiple-source disease registries.

关键词： capture-recapture methods log-linear models logistic models models, statistical registries

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Allowing for non-ignorable non-response in the analysis of voting intention data

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JOURNAL OF THE ROYAL STATISTICAL SOCIETY SERIES C-APPLIED STATISTICS 1999年第4期48卷 563-577页

作者： Smith, PWF Skinner, CJ Clarke, PS Univ Southampton Dept Social Stat Southampton SO17 1BJ Hants England

We apply some log-linear modelling methods, which have been proposed for treating non-ignorable non-response, to some data on voting intention from the British General Election Survey. We find that, although some non-ignorable non-response models fit the data very well, they may generate implausible point estimates and predictions. Some explanation is provided for the extreme behaviour of the maximum likelihood estimates for the most parsimonious model. We conclude that point estimates for such models must be treated with great caution. To allow for the uncertainty about the non-response mechanism we explore the use of profile likelihood inference and find the likelihood surfaces to be very flat and the interval estimates to be very wide. To reduce the width of these intervals we propose constraining confidence regions to values where the parameters governing the non-response mechanism are plausible and study the effect of such constraints on inference. We find that the widths of these intervals are reduced but remain wide.

关键词： log-linear models missing data polling data profile likelihoods

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Capture-recapture method for estimating misclassification errors: application to the measurement of vaccine efficacy in randomized controlled trials

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INTERNATIONAL JOURNAL OF EPIDEMIOlogY 1999年第1期28卷 113-116页

作者： Simondon, F Khodja, H Inst Francais Rech Sci Dev Cooperat Infect Dis Res Unit Montpellier France

Background The measure of efficacy is optimally performed by randomized controlled trials. However, low specificity of the judgement criteria is known to bias toward lower estimation, while low sensitivity increases the required sample size. A common technique for ensuring good specificity without a drop in sensitivity is to use several diagnostic tests in parallel, with each of them being specific. This approach is similar to the more general situation of case-counting from multiple data sources, and this paper explores the application of the capture-recapture method for the analysis of the estimates of efficacy. Method An illustration of this application is derived from a study on the efficacy of pertussis vaccines where the outcome was based on greater than or equal to 21 days of cough confirmed by at least one of three criteria performed independently for each subject: bacteriology, serology, or epidemiological link. log-linear methods were applied to these data considered as three sources of information. Results The best model considered the three simple effects and an interaction term between bacteriology and epidemiological linkage. Among the 801 children experiencing greater than or equal to 21 days of cough, it was estimated that 93 cases were missed, leading to a corrected total of 413 confirmed cases. The relative vaccine efficacy estimated from the same model was 1.50 (95% confidence interval: 1.24-1.82), similar to the crude estimate of 1.59 and confirming better protection afforded by one of the two vaccines. Conclusion This method allows supporting analysis to interpret primary estimates of vaccine efficacy.

关键词： efficacy misclassification capture-recapture log-linear models pertussis vaccine

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Discrete-time discrete-state latent Markov models with time-constant and time-varying covariates

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JOURNAL OF EDUCATIONAL AND BEHAVIORAL STATISTICS 1999年第2期24卷 179-207页

作者： Vermunt, JK Langeheine, R Bockenholt, U Tilburg Univ Dept Methodol Fac Social & Behav Sci NL-5000 LE Tilburg Netherlands Tilburg Univ Work Org Res Ctr NL-5000 LE Tilburg Netherlands Univ Kiel Inst Sci Educ Dept Educ & Psychol Methodol D-24098 Kiel Germany Univ Illinois Dept Psychol Champaign IL 61820 USA

Discrete-time discrete-state Markov chain models can be used to describe individual change in categorical variables. But when the observed states are subject to measurement error, the observed transitions between two points in rime will be partially spurious. Latent Markov models make it possible to separate true change from measurement error. The standard latent Markov model is, however, rather limited when the aim is to explain individual differences in the probability of occupying a particular state at a particular point in time. This paper presents a flexible logit regression approach which allows to regress the latent states occupied at the various points in time on both time-constant and time-varying covariates. The regression approach combines features of causal log-linear models and latent class models with explanatory variables. In an application pupils' interest in physics at different points in time is explained by the time-constant covariate sex and the time-varying covariate physics grade. Results of both the complete and partially observed data are presented.

关键词： categorical data EM algorithm latent class analysis latent Markov models log-linear models logit models measurement error modified Lisrel approach modified path analysis approach panel analysis time-varying covariates

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The nature of mother and toddler problems. (ii) Patterns of disturbance and disadvantage

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EUROPEAN CHILD & ADOLESCENT PSYCHIATRY 1999年第2期8卷 92-106页

作者： Stretch, DD Nicol, AR Davison, I Fundudis, T Univ Leicester Div Child Psychiat Greenwood Inst Child Hlth Leicester LE3 0QU Leics England

Prevalence estimates for psychiatric disturbance in mothers and their 2 1/2 year old children and the variations in prevalence associated with marriage quality, social class and the child's developmental level are presented. It was found that both the mother's psychiatric disturbance, and more specifically, depression were associated most strongly with child disturbance, poor marriage quality and low child developmental level. For toddler disturbance, the strong associations were with type and severity of disturbance in mother, social class, marriage quality and low developmental quotient.

关键词： child behaviour problems maternal psychiatric disturbance prevalence log-linear models

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