bluuebunny/crossref_metadata_2025_split huggingface dataset:
Small Sample Distribution and Power of the Binomial Index of Dispersion and Log Likelihood Ratio Tests
Authors: Bennett B. M. , Kaneshiro C. 
Published: April 2007

AbstractThis paper considers the exact distribution of the X2 index of dispersion and ‐2 log (likelihood ratio) tests for the hypothesis of homogeneity of c independent samples from a common binomial population. The exact significance levels and power of these tests under ‘logit’ alternatives are compared numerically for the cases: c = 3, 4, 5 and various sample sizes. n1 = 5,10 for i = 1,…, c.
Application of some Multivariate Analysis Techniques to Data on Effect of Air‐Pollution on Morbidity
Authors: Sahai H. 
Published: April 2007

AbstractIn this article an attempt has been made to analyze the data obtained from an air‐pollution study to investigate the effects of the levels of air pollution exposure in causing morbidity, using some multivariate statistical techniques. Considering the importance of the theoretical aspect of the problem, the usual theory related to the application of these methods has also been described.
The Probability Density Functions of the Contingency Coefficients, defined by KRAMER and PEARSON, in a 2‐Dimensional Frequency Distribution of Grouped Bivariate Normal Variables. I
Authors: Knauer S. 
Published: April 2007

AbstractTwo general measures for the degree of association in a contingency table are the contingency coefficients defined by PEARSON and KRAMER. In the case of a standardized bivariate normal distribution with correlation coefficient of the variables, whose realizations constitute the rows and columns of the table, the density functions of the two listed association measures are derived.
An Application of the Logistic Distribution to the Analysis of a Measles Epidemic
Authors: Slymen D. J. , Woolson R. F. , Myers M. G. 
Published: April 2007

AbstractThe relationship between the development of measles and age at immunization and time since immunization is examined using a trichotomous logistic distribution with maximum likelihood estimation of the parameters. The first and second partial derivatives used in the estimation scheme are presented.
Expected Error Rates for Logistic Regression Versus Normal Discriminant Analysis
Authors: McLachlan G. J. , Byth K. 
Published: April 2007

AbstractThe expected error rates associated with using the allocation rule based on logistic regression are derived in the context of two multivariate normal populations with a common covariance matrix and compared with the corresponding error rates of the classical rule based on this normality assumption. It is shown in terms of the actual sizes of the asymptotic expected error rates that the performance of the logistic procedure does not fall far short of the normality based method, even for widely separated populations. This latter result is not obvious from previously available work on the asymptotic relative efficiency of the logistic procedure.
A New Nonparametric Approach to the Comparison of K Independent Samples of Response Curves II: A K Sample Generalization of the FRIEDMAN Test
Authors: Lehmacher W. 
Published: April 2007

AbstractA K sample generalization of the FRIEDMAN test (1937) is introduced which can be used as a nonparametric procedure for testing the homogeneity of the profiles of K independent samples of response curves measured at T identical points of time. While a similar procedure in LEHMACHER & WALL (1978), section 3, is based on T combined tests, each of them at level a/T, here a finite and asymptotic test is presented which is based on a single test statistic. The application of the new multivariate test is illustrated by the same numerical example as in LEHMACHER & WALL (1978). The properties of this test are discussed and compared with the combined test mentioned above.
Estimation of Attributable Risk in the Presence of Confounding
Authors: Ejigou Ayenew 
Published: April 2007

AbstractLEVIN's attributable risk due to a risk factor is estimated in the presence of confounding in the retrospective study context. The crude attributable risk is decomposed into the attributable risk due to a risk factor and a bias factor which is shown to vanish only when the confounding factor is unassociated to either the risk factor or the Disease or to both. Asymptotic tests are provided for testing interaction, and an appropriate pooled estimate is derived when constancy of partial attributable risks prevails over the levels of the confounding factor.
Two criteria for the comparison of multiple arrangements of experiments and their use to answer the question: Is it better to compare p treatment groups with p controls or with a single control
Authors: Horn M. 
Published: April 2007

AbstractIn experimental situations examining the effectiveness of p(p>1) treatments by comparing treated groups and untreated controls the following question arose: Which experimental arrangement is more appropriate, an arrangement A1 using for the p comparisons only one single control, or an arrangement A2 using for every comparison another control. To answer this question two criteria are formulated. The first criterion takes into consideration the expected numbers of type I and type II errors, and the second criterion the probabilities of type I and of type II errors. According to the first criterion A1 and A2 do not differ, generally. According to the second criterion A1 with the comparison of means of normal distributed variables is better than A2. Pooling of all p controls is better than A2 according to both criteria. A1 is better also according to the often used experimentwise type I error rate. The formulated criteria have some analogy to those of MILLER (1966). It may be possible to use them not only for comparing experimental arrangements but also tests.
Construction of Equi‐replicated Balanced Block Designs with Block Sizes Exceeding the Number of Treatments
Authors: Ceranka B. , Mejza S. 
Published: April 2007

AbstractIn this note it is shown that the block design with incidence matrix Ñ = [NN… N], where N = c1hNh + coh (11′–Nh). coh and c1h are any non‐negative integers and Nh,h = 1, 2,…,p, are incidence matrices of balanced incomplete block designs with the same number of treatments t, is a balanced block design with the block sizes exceeding the number of treatments. In derivation the matrix M0, introduced by CALIński (1971) is utilized.
Analyse des pedigrees et calcul des coefficients d'identité par les arbres géniques
Authors: Vu Khang J. Tien , de Rochambeau H. , Chevalet C. , Gillois M. 
Published: April 2007

AbstractTwo genes in a pedigree are identical by descent if they are two copies of a common ancestor gene. To obtain an unambiguous definition of the set of genes, at some autosomal locus, any gene is defined as an ordered pair of zygotes: the zygote who carries the gene, and the parent who transmitted it. The natural ordered structure on the set of zygotes yields an ordered structure upon the set of genes. Any event of the mendelian segregation splits down the set of genes into non‐overlaping classes of identical genes: when considered as an ordered sub‐set of genes, each class is shown to have the algebraic properties of a tree. Given a sub‐set 𝔗 of genes, a family of exclusive events ensuring identity between all genes of 𝔗 is identified as a family of genic trees with some property. This relationship between segregational events and genic trees is extended to the case where two sub‐sets 𝔗 and 𝔗′ of genes are considered together. As a consequence, a general method is obtained to compute either identity coefficients involving any number of genes splitted into one or two identity classes, or the fifteen coefficients defined among four genes, whichever the relationships between zygotes and genes might be. Using this approach to deal with the allelic structure in a set of genes carried by related zygotes is suggested.
A Mathematical Model for Extrachromosomal Heredity in Somatic Cells, Exemplified by Liver Cells
Authors: Hopfenmüller W. 
Published: April 2007

AbstractThe cytoplasm of a zygote is observed on the somatic way of evolution up to the organ. For mitochondria, which are the most important cellcomponents for the extranuclear heredity, a model of evolution for liver cells with its computer programs was developed.
Four Applications of a Bivariate Pareto Distribution
Authors: Hutchinson T. P. 
Published: April 2007

AbstractThe following model, of “latent structure” type, is considered: in each subpopulation, X and Y are random variables drawn independently from the same exponential distribution, and the parameter of the exponential distribution varies between subpopulations with a Gamma density. Over the whole population, X and Y are then positively correlated, and jointly have a bivariate PARETO distribution. Four examples show how this distribution is useful in analysing ordered contingency tables in which the two dimensions can be regarded as alternative measures of the same thing: the injuries to the two drivers in a road accident, or the severity of a lesion present in a patient as assessed by two physicians, for instance.Two extensions are considered: (a) allowing X and Y to have Gamma distributions, with each subpopulation having the same shape parameter but different scale parameters; (b) allowing the scale parameter for Y to be correlated with the scale parameter for X, rather than being identical to it. A new bivariate distribution with three shape parameters is derived, expressed in terms of a generalised hypergeometric function.
The Sensitivity of the Stationary Age Class Distribution o Changes in the Life History Components
Authors: Gregorius H.‐R. 
Published: April 2007

AbstractThe influence of the various components of the life history on the stationary age class distribution of a population was studied by applying the Leslie matrix model and then considering the single age class frequencies as well as the average age and the cumulative age class distribution in the stationary state.Since, for fixed survival probabilities, the effects of the (age specific) fecundities were shown to be already expressed by the (ultimate) growth rate, this investigation was concentrated on the influence of the survival probabilities and the growth rate. After having supplemented some useful details concerning the dependence of the growth rate on the life history and introduction of the shift concept as an interpretation of cumulative distributions, the mathematical results could be given a biologically intelligible meaning:An increase in the growth rate for fixed survival probabilities is followed by a shift of all age class frequencies to earlier ages. Whereas age specific changes in fecundity do not result in age specific changes in the stationary age class distribution, increases in survival up to and including age k, say, do exhibit such changes in that they cause a shift of age class frequencies at least from those ages exceeding k to earlier ages.
Group Divisible Second Order Rotatable Designs
Authors: Singh M. 
Published: April 2007

AbstractThe Group Divisible Rotatable (GDR) designs are the designs in which the factors get divided into groups such that for the factors within group, the designs are rotatable. In the present paper we have obtained a series of Group Divisible Second Order Rotatable designs, by decomposing the v‐dimensional space corresponding to v‐factors under consideration into three mutually orthogonal spaces. We have given the least squares estimates of the parameters, the analysis and construction of such designs.
Quantitative Equations for the Calculation of Ideal Values of Intra‐ and Extraerythrocyte Ion Contents of Human Blood after Addition of Roentgenographic Contrast Media
Authors: Jäger B. , Mangelsdorf R. , Bollmann G. 
Published: April 2007

AbstractNormalized quantitative equations were derived to permit the calculation of intra‐ and extra‐erythrocyte ionic contents of human blood following the in vitro application of contrast media. These formulae allow the ionic contents to be computed, which should be present in plasma and erythrocytes if, after contrast medium administration, no ionic shifts occur other than electrolyte unbalance as induced by changes in water content. The equations are also applicable when other aqueous solutions are added to human blood.
A Note Concerning “Some Nonparametric Tests of Predicted Order”
Authors: Hsu L. M. 
Published: April 2007

AbstractSARRIS and WILKENING (1977) have recently proposed some non‐parametric trend tests, which they view as extensions of MOSTELLER'S test of predicted order. The present paper notes some errors in SARRIS and WILKENING's determination of significance levels for these tests, and describes how these errors may be corrected.
Bivariate Sign Tests Sensitive to Homeo‐ and Heteropoetic Treatment Effects
Authors: Kohnen R. , Lienert G. A. 
Published: April 2007

AbstractStarting fromNpaired differences of a continuous variable, BENNETT's (1962) bivariate sign test is identified as a test against so called homeopoetic treatment effects (or location shifts in one or both variablesXandY). As a complement, a new sign test is identified to be sensitive to so called heteropoetic treatment effects (shifts in dispersion). Both tests are shown to be important in biomedical and psychosocial research. A numerical example is given from psychopharmacology using the new bivariate sign test.
Basic distribution theory for nonparametric gini‐like measures of location and dispersion
Authors: Heilmann W. ‐R. 
Published: April 2007

AbstractIn the present paper, the distributional properties of two nonparametric estimators of location and dispersion which are patterned after GINI'S “media differenza”, are studied. Since these are special U‐statistics, we can make use of known results to some extent. By some computed examples, the differences to the mean value and the standard deviation become apparent.
C. R. Rao's minque under four two‐way anova models
Authors: Kleffe J. 
Published: April 2007

AbstractThis paper presents C. R. RAO'S MINQUE along with their sample variances under four normal two‐way ANOVA models. The resulting formulae are similar to the ANOVA sums of squares, equally easy to handle with and may also serve to calculate restricted maximum likelihood estimates in a highly efficient way.
On connectedness of ordinary two‐way elimination of heterogeneity designs
Authors: Baksalary J. K. , Kala R. 
Published: April 2007

AbstractFor certain subclasses of ordinary, not necessarily equireplicated, two‐way elimination of heterogeneity designs, necessary and sufficient conditions are established for row connectedness and column connectedness of a design to imply its connectedness. The criteria obtained strengthen earlier results pertaining to this problem.
A model‐independent approach to the theory of experimental designs and a special discussion of bib. i general definition and designs with one or two block factors
Authors: örfer G. Herrend , Rasch D. 
Published: April 2007

AbstractExperimental designs are definded by introducing an assignment matrix Z. It is shown by block designs and double block designs that using Z or an operator on Z otherwise defined, well known designs can be got as special cases. Till now we didn' find an experimental design which could not be defined by our matrix Z. The definitions of properties of experimental designs can be given independently of the model of the statistical analysis. This is shown for the property of balance of block designs.
On the mean square error associated with adaptive generalized ridge regression
Authors: McLachlan G. J. 
Published: April 2007

AbstractSome numerical results are presented for generalized ridge regression where the additive constants are based on the data. The adaptive estimator so obtained is compared with the least‐squares estimator on the basis of mean square error (MSE). It is shown that the MSE of each component of the vector of ridge estimators may be as low as 47.1% of the variance of the corresponding component of the least squares vector or as high as 125.2%.
Estimation of random regression parameters
Authors: Wimmer G. 
Published: April 2007

AbstractThe problem of the best linear unbiased estimation (BLUE) of random regression parameters is considered. It is proved that increasing informations about the mean value of the parameters both extend the class of estimable linear functionals and improve on the estimation. In all investigated cases the uniqueness of BLUE is proved. In the case of known mean values the BLUE is shown to be numerically equivalent with the MMSEE almost everywhere. A numerical example shows the improvements of BLUE due to increasing informations about the mean values of the parameters.
Tests for profile analysis of paired curves based on friedman ranking methods
Authors: Lehmacher W. 
Published: April 2007

AbstractTwo nonparametric tests are proposed for the comparison of a paired sample of response curves with T congruent time points. The first procedure rank transforms each curve and tests the homogeneity of the resulting pair of averaged rank vectors. The second procedure rank transforms each pair of curves and tests the homogeneity of the related pair of averaged rank vectors. The first test detects only pure interactions; the second test checks if any difference exists between the rank curves. Both tests are presented in finite and asymptotic as well as in combined (by T singular tests) and multivariate form.
On a stochastic model of a molecular genetic system capable of differentiation and reproduction of the initial state
Authors: Tchuraev R. N. 
Published: April 2007

AbstractA model of the system, consisting of a cyclic 3‐operonic subsystem, related to a 2‐operonic trigger by direct and feedback connections, is built. The operons of this system are functionally connected by repressers. The basic postulates are: a) the repressers are stable; b) during cell division each molecule of represser and respective mRNA has equal probability to find itself in any daughter cell. Computer simulation demonstrates that after few cell divisions, analogues of somatic cell, maintaining the system for some successive divisions, and of generative cells, where by the system returns to the initial state, appear. A scheme of molecular genetic control system, producing a lot of different cell types in course of successive cell divisions, is proposed.
A model of niche overlap and interaction in ecological systems
Authors: Steinmüller K. 
Published: April 2007

AbstractEcological niches are the result of ecosystem element (compartment) interaction under the influence of environmental factors. The competence model is devised to map this interaction. It includes the assumption of an overall physiological state of a compartment depending only on intensive environmental factors, expressions for the adaptedness and competence of the compartment in interaction. Consequently, niches are environmental factor domains of superior competence. The situation of niches (niche structure) and competence maxima are extensively studied in the fundamental case of two interacting compartments and in the special case of n concentric compartments. The impact of one immigrating compartment is discussed. All detailed investigations made involve only one intensive environmental factor and the special assumption of similar physiological state functions of all compartments.
An intrinsic rank test for k independent samples
Authors: Kannemann K. 
Published: April 2007

AbstractConsiderations on the sensitivity of the KRUSKAL‐WALLIS Analysis of Variance by Ranks suggest an alternative method that is less sensitive to spurious interchange of ranks and tied ranks yet offers sufficient power. The Intrinsic Rank Test for k Independent Samples is proposed in this sense as an alternative method to the KRUSKAL‐ WALLIS test. The Intrinsic Rank Test is based on rank information, but the criterion ranks (intrinsic ranks) are not directly derïved from the observations, but rather indirectly, by means of a further transformation, from the ordinal ranks assigned in the usual manner. The incidence of the intrinsic ranks upon the k samples is then used to calculate a X2‐like test statistic, which is readily evaluated with the Gamma distribution.
A contribution to spline‐regression
Authors: Dathe E. M. , Müller P. H. 
Published: April 2007

AbstractConsidered are polynomial spline‐regressions by which functions with individual behaviour over parts of their domain may be approximated (in square mean) in a favourable manner by successive polynomials. Concerning the connections of the individual polynoms different conditions may be imposed as to continuity and smoothness. Beside of the calculation of the regression parameters essential results are the construction of confidence regions for the regression function and the formulation of tests for special dependence. Hints for practical application are given and a concrete example from agriculture is presented.
On classifying observations when one population is a mixture of normals
Authors: Lachenbruch P. A. , Broffitt B. 
Published: April 2007

AbstractSome simple models for the mixture of distribution problems are considered. Two possible alternatives to the rather complex optimal discriminant function rule are mentioned. The performance of the BC method is never as satisfactory as the QDF method and in some cases it is far worse than the QDF method. The QDF can be used whenever sufficient numbers of observations are available to provide reasonably good estimates of means and covariances.
A concept of a general computer program for the iterative calculation of maximum likelihood estimators with application to qualitative dose response analyses
Authors: Pahnke K. , Stucky W. 
Published: April 2007

AbstractIn this article we describe the construction of a general computer program for the iterative calculation of maximum likelihood estimators. The program is general in the sense that it allows the maximization of any given likelihood function. The user only has to write a subroutine LKLHD, in which the special likelihood function and their first and second derivatives will be calculated. This subroutine is an input parameter of the optimization program. This enables the user to employ one main program for the maximization of various likelihood functions. This advantage will be shown for the evaluation of qualitative dose response relationships (quantal assays: probit‐, logit‐analysis).
Point estimation in quantal response models
Authors: Schumacher M. 
Published: April 2007

AbstractIn this article least‐squares‐ and maximum‐likelihood‐estimators in quantal response models are presented in a standardized terminology. The large sample properties are derived and the convergence properties of the Newton‐Raphson‐ and the Scoring‐method for the iterative solution of the likelihood equations are investigated. Finally, it is shown that the iterative least‐squares estimation methods are equivalent to the method of scoring.
Use of the tetrachoric correlation model in assessing clinical tests
Authors: Bennett B. M. 
Published: April 2007

AbstractCategorical data on n patients are classified according to the results on an initial clinical test T, and also with respect to a subsequent and definitive diagnosis D. In this paper the sensitivity (=), specificity (=) and predictive values (=v) are discussed with reference to the tetrachoric correlation model based on the bivariate normal density (e.g. PEARSON, 1901; KENDALL and STUART, 1972, II, p. 317). The result of HAMDAN (1970) concerning the equivalence of the tetrachoric rt and the maximum likelihood estimate of the correlation coefficient is utilized in this paper to obtain a test of significance concerning rt, and also the relation between the tetrachoric function w and the relative risk ψ for the 2X2 table.