摘要:

Three experiments involving the growth of tumor cells in an organ culture system are described. The fraction of labeled mitoses, the labeling index, and the grain count are measured in each of these experiments. The data and the statistical analyses involving skewed logistic regression, branching process theory, and two-phase linear regression are presented.

ISSN:0162-1459    

DOI:10.1080/01621459.1982.10477839

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

Nonadditivity in a two-way table with one observation per cell may be due either to row- or to column-related nonhomogeneous variance or to interaction between the row and column factors. A general model that can detect both of these types of nonadditivity is discussed. The data alone are not sufficient to distinguish between interaction and row- or column-related nonhomogeneous variance when there is one observation per cell. A study of the fitted coefficients in the proposed model together with the scientific background of the problem can, however, provide the data analyst with the information necessary to develop a useful interpretation for the observed nonadditivity. Examples are included to illustrate the proposed methodology. In one example, involving the effects of four varieties of wheat in 13 locations, it is shown that the variety-related nonhomogeneous variance detected by several authors is more usefully interpreted as a level-dependent interaction due to the differences among the yields of the different varieties of wheat being larger in those locations that have higher yields.

ISSN:0162-1459    

DOI:10.1080/01621459.1982.10477840

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

Most monthly time series that represent a total of some variable for each month contain calendar effects due to changing month length, day-of-the-week effects, and holidays. It is important to remove the calendar variation to allow an effective assessment of the variation due to important factors. New procedures for calendar adjustment are presented in this article. A plausible model for the daily data is used to derive a model for the monthly data in which the power transformed, month-length corrected data are equal to trend plus seasonal plus calendar plus irregular. The procedure for fitting the calendar component in the monthly model is (a) divide the aggregated monthly data by month length and multiply by 30.4375, the average month length; (b) choose a power transformation; (c) remove trend and seasonal components; (d) estimate the calendar parameters by robust regression. Since the model is only a hypothesis it is important to check its validity. This can be done by various residual plots in the regression analysis and by using spectrum analysis and time-domain graphical methods to detect residual calendar effects in the adjusted series. This approach is compared to the X-11 calendar estimation procedures.

ISSN:0162-1459    

DOI:10.1080/01621459.1982.10477841

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

Two production-function models with error components for time and firms and a heteroscedastic disturbance are proposed. Unlike previous models, these two permit the variance of output to increase or decrease as one of the inputs is increased. When the models and some suggested estimators are applied to the pastoral zone of eastern Australia, the results indicate that labor, water, and possibly fencing, are likely to reduce the variance of wool production; and that sheep, and buildings and land, are likely to increase the variance.

ISSN:0162-1459    

DOI:10.1080/01621459.1982.10477842

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

ISSN:0162-1459    

DOI:10.1080/01621459.1982.10477843

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

Symbols whose sizes code a variable are often superimposed on a map to show how the value of the variable changes geographically. In many cases the areas of the symbols are proportional to the values of the variable. But previous psychological experiments indicate that people's judgments of area typically are not proportional to area, but rather to area raised to a power less than one. In many of these studies, however, the symbols are presented one at a time. Here we describe an experiment that tests whether this experimental laboratory result extends to statistical maps. We had 24 viewers judge sets of circles presented simultaneously, either with or without maplike grid ticks, labels, scale, and border. With these multiple-circle displays, judgments were related to actual area by power functions with an average exponent close to one, implying that it is appropriate to code symbols by area on statistical maps.

ISSN:0162-1459    

DOI:10.1080/01621459.1982.10477844

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

摘要:

This paper puts forth the view that diversity is an average property of a community and identifies that property as species rarity. An intrinsic diversity ordering of communities is defined and is shown to be equivalent to stochastic ordering. Also, the sensitivity of an index to rare species is developed, culminating in a crossing-point theorem and a response theory to perturbations. Diversity decompositions, analogous to the analysis of variance, are discussed for two-way classifications and mixtures. The paper concludes with a brief survey of genetic diversity, linguistic diversity, industrial concentration, and income inequality.

ISSN:0162-1459    

DOI:10.1080/01621459.1982.10477845

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

ISSN:0162-1459    

DOI:10.1080/01621459.1982.10477846

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

ISSN:0162-1459    

DOI:10.1080/01621459.1982.10477847

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor

ISSN:0162-1459    

DOI:10.1080/01621459.1982.10477848

出版商:Taylor & Francis Group    

年代:1982

数据来源: Taylor