bluuebunny/crossref_metadata_2025_split huggingface dataset:
MINQUE and ANOVA Estimator for One‐way Classification ‐ a Risk Comparison
Authors: Ahrens H. 
Published: April 2007

AbstractFor the one‐way classification in unbalanced case MINQUEstimator for components of variance are given in a more explicit form than it is done in the paper from C. R. RAO (1971). By means of the risk functions we compare MINQUE and ANOVA estimator. For given nj‐patterns angular ranges in the positive quadrant are given where MINQUE is better than ANOVA estimator. A special nj‐pattern and one parameter δ0 is found for which MINQUE is uniformly better than ANOVA. Limit values are given for MINQUE for δ0 = ∞ and δ0 = 0 and their relations to the ANOVA estimator are considered. The coincidence between MINQUE and ANOVA for balanced case is verified. Extensive numerical studies for real data are carried out which stimulated the search for a fixpoint δ as a point for which the distance to the initial parameter δ0 is as small as possible.
Eine neue Interpretation des HELLMICHschen Maßes K und seine Anwendungen
Authors: Börzsönyi L. 
Published: April 2007

AbstractFrom the examination of the properties of symmetry of the correlation functions it appears that the asymmetrical functions contain information capability to be used with advantage for the characterization of causal effects. The paper describes a new interpretation of the K measure of HELLMICH as well as its application in the field of investigation of connections. Computer calculations carried out on plant and human populations justify the use of the introduced measure. Concrete results are presented with respect to two maize diseases “stalk rot” and “ear rot”; further a completely analogous problem to examine the relation between diabetes and high blood pressure is outlined.Finally some remarks are made on further investigation of measuring numbers and application in a broader sense.
A Two Sample CRAMÉR‐VON MISES Test for Randomly Censored Data
Authors: Koziol J. A. 
Published: April 2007

AbstractA CRAMÉR‐VON MISES type statistic is introduced for testing the equality of the underlying survival distributions of two populations when observations are subject to arbitrary right censorship. The statistic is appropriate in testing problems where a two‐sided alternative is of interest. The asymptotic distribution of the statistic is found; under certain circumstances, the limiting distribution coincides with that of a one sample CRAMÉR‐VON MISES type statistic for randomly censored data investigated previously. Approximations to the asymptotic distribution are discussed; an example is given.
A Mathematical Model for Extrachromosomal Heredity
Authors: Hoppenmüller W. 
Published: April 2007

AbstractDuring embryogeny the components of the cytoplasm of a zygote are subject to certain irregularities. This has been investigated with the aid of some probability models and distribution functions. For mitochondria, which are the most important cell components with respect to extra‐chromosomal heredity, a four‐phase model with computer programs was developed.The complete arithmetical results total 15,000 pages from a fast printer. For the jobs a CPU‐time of 500 hours, using a SIEMENS 4004 system, was required.
Characterization of the WEIBULL Distribution by Properties of Order Statistics
Authors: Janardan K. G. , Taneja V. S. 
Published: April 2007

AbstractLet X1:n, X2:n, X3:n…, Xn:n be the order statistics of n independent random variables with the common (absolutely continuous strictly increasing) distribution function F. The main results given in this article are:

For any fixed r and two distinct numbers s1 and s2 (1<r<s1<s2≦n) the distributions of Vi and Wi (defined in (1.11) and (1.12) are identical for i = 1,2 iff F(x) is WEIBULL (1.2).
The statistics D1 and D2 (as in (1.8) and (1.9)) are independent iff F(x) is WEIBULL (1.2).
The statistics Ui (1≦j≦n−1) and Xi:n (i ≦ j) are independent iff F(x) is WEIBULL (1.2).
Let X, X1, X2, …, Xk be random variables such that
magnified image

These conditions are necessary and sufficient for F(x) to be WEIBULL.
An Unbalanced Mixed Model with Random Effects Having Unequal Variances
Authors: Hussein M. , Milliken G. A. 
Published: April 2007

AbstractConsider the mixed model where xijk's are known constants, βk are unknown parameters and ai, eij are random variables independently and normally distributed with zero means and variances σdi and σ2 respectively, where it is assumed that the di's are known (di >0). This paper presents procedures for estimating the variance components σ, σ2, for testing the hypothesis σ = 0, and for making transformations to random variables with uncorrelated errors and constant variances in order to estimate as well as to test hypothesis concerning the βk's in the model.
The Heritability of Difference Scores when Environments are Correlated
Authors: Weiss V. 
Published: April 2007

AbstractThe statistical analysis of difference scores (contrasts) is a fundamental problem in all learning, feeding, and training experiments and tests, and in longitudinal studies of growth and development. Outgoing from the analogy between the mathematical models of classical psychological test theory and quantitative genetics, as well as between the parameters reliability and heritability of these models, the present paper derives the formulas of the heritability of difference scores in general cases where it is not assumed that environmental deviations on distinct tests and measurements are uncorrelated. Contrary to the assertion, made by FELDMAN and LEWONTIN, heritabilities in the broad sense can be used as ideal weighting factors in long‐range personnel index selection. Longitudinal studies of twins and the cotwin method are powerful experimental designs to estimate heritabilities of differences.
Statistical Analysis of Joint Effects of Major Genes and Polygenes in Quantitative Genetics
Authors: Tan W. Y. , D'Angelo H. 
Published: April 2007

AbstractIn this paper we analyze a quantitative genetic character which is controlled by both major genes and polygenes. Assuming that there are no epistatic effects, no linkage and no genetic‐environmental interactions, we follow TAN and CHANG (1972) to derive the probability distributions for segregating populations. The numbers of major genes and polygenes, and the additive and dominance effects of major genes and polygenes are then estimated by using the procedures developed in TAN and CHANG (1972) and the POWELL‐FLETCHER search procedure for maximum values. In this paper, we consider the case involving data from P1, P2, F2, B1 (Backcross to P1) and B2 (Backcross to P2) as this type of experiment is common in practical applications. The analyses are applied to a simulated model generated by using binomial, multinomial and normal variables and to the data of an experiment on kernel weight of sorghum plant provided to the authors by Professor GEORGE H. L. LIANG of Kansas State University. The analysis of these data indicate clearly that the method derived in this paper is useful and desirable.
On the Effects of Departure from Normality on theF‐Ratios in a Nested Random Effect Model by Mixture of Normals
Authors: Tan W. Y. , Wong S. P. 
Published: April 2007

AbstractIn this paper we consider the following nested random effect modelmagnified imagewhere the αi's, the βij's and theeijkare independent random variables. By assuming that these variables follow a mixture of two normal densities, we study the effects of departure from normality on the classical JT‐tests for variance components. It is shown that the departure from normality has little effects on the type 1 error and the power function; this indicates that the classicalF‐tests are quite robust with respect to departure from normality.
Regarding the Optimality of the Formula \documentclass{article}\pagestyle{empty}\begin{document}$ \frac{{n_0 }}{n} = \sqrt p $\end{document} for the Ratio of Sample Sizes of a Control and of p Treated Groups
Authors: Horn M. 
Published: April 2007

AbstractFINNEY (1955) recommended without argument the ratio \documentclass{article}\pagestyle{empty}\begin{document}$ \frac{{n_0 }}{n} = \sqrt p $\end{document} where p is the number of treated groups to be compared with a control and n and n0 are the sizes of the treated samples and of the control. The question is does this allocation result in an optimum, anywise. RASCH, HERRRENDörfer und BOCK (1972) asserted that this ratio with t‐tests is followed by maximal expected values of the t‐statistics. Here is shown that this allocation with t‐tests provides minimal comparisonwise type II error rates. Moreover, with the t‐test and the DUNNETT test the mean number of type II errors becomes a minimum. Nearly optimal is this allocation with the t‐test and the DUNNETT test regarding the experimentwise type II error rates. Not optimal is this allocation regarding the experimentwise type I error rates.
Estimation of BAYESian Confidence Intervals for the Product of Conditional Survival Probabilities
Authors: Schmitz H. 
Published: April 2007

AbstractA model is derived to estimate the survival probability of a time interval when censorings occur. The time interval is divided into partial intervals in order to obtain the conditional survival probabilities, each of which is a parameter of a Binomial distributed random variable. To allow for the dependence between the events in the different intervals these parameters are transformed. Corresponding a priori density functions are formulated regarding both the Bayesian uniform distribution and the special model. The a posteriori density function is derived for the product of the conditional survival probabilities, and formulae for the BAYEsian confidence interval and the expectation are given. Lower and upper bounds for the confidence interval and the expectation are derived. Some examples are given to compare the results with other methods.
The Influence of External Real and White Noise on the LOTKA‐VOLTERRA Model
Authors: Arnold L. , Horsthemke W. , Stucki J. W. 
Published: April 2007

AbstractThe behaviour of a marginally stable predator‐prey system, the LOTKA‐VOLTERRA model is analyzed under the influence of parameter fluctuations. The cases of white and real noise are studied separately. It is shown that for white noise no stationary solution exists, but even for time tending to infinity explosion occurs only with zero probability. In the case of real noise the class of noise processes that permit a stationary solution is characterized by their spectral density. It turns out that this class consists of all stationary processes that do not contain the eigenfrequencies of the LOTKA‐VOLTERRA system.It is shown that for all other real noise processes a resonance phenomenon occurs and the solutions grow unboundedly.
Estimation of Interplant Dependence in a Linear Planting Scheme
Authors: Gleeson A. C. , McGilchrist C. A. 
Published: April 2007

AbstractA maximum likelihood procedure is developed to estimate the dependence relations between plants at equal distances along a row, by fitting simultaneous bilateral models to the observations. Where there is more than one characteristic measured on each plant, a simultaneous bilateral vector model can be fitted by maximum likelihood procedures. The latter model also applies when one characteristic is measured on each plant in a two‐dimensional planting array where interplant distances within each row are equal but interrow spacing varies. The estimation is particularly suited to the small sample situation.
The Non‐Central Negative Binomial Distribution
Authors: Ong S. H. , Lee P. A. 
Published: April 2007

AbstractThe non‐central negative binomial distribution is derived by mixing the POISSONdistribution with a certain BESSELfunction distribution, or the negative binomial distribution with the POISSONdistribution. Some properties of the distribution are discussed, including a characterization. The fitting of the distribution to some data are given together with the efficiency for various procedures of estimation.
Besetzungsmodelle
Authors: Herrmann H. 
Published: April 2007

AbstractStarting with the classical occupancy with boxes, balls and probabilities for occupying boxes, we employ new models: a ball, which met a box, occupies this box with a probability depending on the size of box content, and ‐ using several kinds of balls ‐ by the composition of the content too. For that purpose several models are constructed with distinctive forms of the conditions.Dealing with these models ‐ they are special MARKOvian chains ‐ we pay attention mainly to the so called first passage time Tz for defined events Z; in particular for certain events Z we have to prove that Tz is a random variable, and have to set up the appropriate probability generating function.
A Multivariate Analysis of Hybridization when Covariance Matrices are Unequal
Authors: Misra R. K. 
Published: April 2007

AbstractNumerous occurrences of natural hybridization have been known in many groups of animals. It has a bearing on growth, nomenclature, speciation, genetics and wildlife management. It is well recognised that demonstration of intermediacy based on several characters makes the identification of hybrids more certain than that based on just a single character, and that differences among the hybrids and the parental populations should be analysed for variations due to the additive genetic (A) and the non‐additive genetic (NA) factors separately. In the present paper (i) it is pointed out that sometimes the assumption that covariance matrices of the hybrids and the parental populations are equal, may not be valid, and (ii) a multivariate method of testing hypotheses analysing differences between the hybrids and the parents, qualified by the A and the NA factors, when covariance matrices are not equal, is submitted.
Robuste schätzungen: Ein anwendungsorientierter Überblick
Authors: Hampel F. 
Published: April 2007

AbstractThe paper offers an introductory survey of the area of robust estimation for applied statisticians, without demanding much mathematics. At first, the most important basic ideas of the robustness theory are explained using an example from the analysis of variance. Then the general reasons for and limits of the “robustification” of statistics are delineated. In particular, the various types of deviations from ideal models, such as gross errors, are discussed and their consequences are pointed out. The next part describes several simple robust estimators and their properties, ending with an outlook on robust estimators in linear models. As an appendix a number of frequent objections to and misunderstandings of robustness theory are discussed, refuted and clarified.
A necessary condition for balance of a block design
Authors: Baksalary J. K. , Dobek A. , Kala R. 
Published: April 2007

AbstractIt is shown that, barring orthogonal designs, a necessary condition for a block design,BD(v, b, N), to beJ‐balanced is that the rows of its incidence matrix,N, are linearly independent. This strengthens the conditionb vknown in the literature as FISHER'S inequality.V‐balanced block designs are also discussed.
Asymptotic and explicit formulae for a non‐markovian model with linear transition rule
Authors: Ismail M. E. H. , Theodorescu R. 
Published: April 2007

AbstractAsymptotic and explicit formulae are obtained for the n‐step stochastic kernel of a special class of non‐MARKOVIAN models with linear transition rule which occur in learning theory, adaption theory, control theory, and biological research.
Simplified formulas for three‐way chi‐square testing
Authors: Lienert G. A. , Wolfrum Christine 
Published: April 2007

AbstractIn order to test against contingency in a 3‐way table, simplified X2‐formulas are given for (1) the general r xcxl‐table, (2) for the rxcx2‐table, (3) for the 2x2xl‐table, and (4) for the 2×2×2‐table. The tests are valid only if a sample of N individuals is observed as to 3 discrete or discretisized (dichotomized) variables which are, under H0, assumed to be totally independent.
Confidence limits for drug‐induced response rates in carcinogenesis experiments
Authors: Wahrendorf J. , Port R. E. 
Published: April 2007

AbstractAnimal experiments in chemical carcinogenesis are often analysed by tests for equal proportions in a 2 × 2 table. Since hereby nothing is said about the power of the tests, we propose to describe the outcome of such an experiment by an upper confidence limit of an adjusted difference between the two response rates.
On the difference between gauss‐markov and least squares estimates
Authors: Scobey P. , Kabe D. G. 
Published: April 2007

AbstractFor the usual full rank univariate least squares regression model y = XB + e, E(e) = 0, E(ee) = A, the equality of the estimates occurs when B‐B* = (XA−1X)−1XA‐1y‐(XX)−1Xy = 0. A necessary and sufficient condition for this equality is that A has some N ‐ k + 1 roots equal where N is the rank of A and k is the rank of X.
Designs for restricted exploration in mixture experiments
Authors: Goel B. S. 
Published: April 2007

AbstractExtreme Vertices designs were developed by MCLEAN and ANDERSON (1966) for situations where components of a mixture are restricted by lower and upper bounds, SNEE and MARQUARDT (1974) and SNEE (1975) gave algorithms to construct optimum designs in these situations. SAXENA and NIGAM (1975) evolved a transformation which provides designs for restricted exploration using Symmetric Simplex designs. In this paper a procedure has been given which provides alternative designs with uniform exploration in constrained mixture experiments. The procedure is illustrated by an example.
Simple, sensitive and on‐line fluorescence monitoring of photodegradation of phenol and 2‐naphthol
Authors: He Yihua , Lv Yi , Hu Jing , Qi Linlin , Hou Xiandeng 
Published: April 2007

AbstractA simple molecular fluorescence spectrometer based on a hand‐held CCD spectrometer was constructed for on‐line monitoring of the photodegradation of pollutants. A high‐pressure Hg vapour lamp was used for the UV photodegradation and simultaneously for the fluorescence excitation. Phenol and 2‐naphthol were selected as the targets for this preliminary study. Using peak fluorescence, figures of merit for monitoring these two hydroxybenzene were obtained. Degradation efficiencies with different homogeneous photocatalyst systems were investigated, including UV only, UV/H2O2 and UV/Fe3+ degradation systems. The kinetics modelling showed that their photodegradation fitted the Langmuir–Hinshelwood model. Results showed that the proposed method is potentially applicable to both on‐line real‐time monitoring and field analysis. Copyright © 2007 John Wiley & Sons, Ltd.
Simultaneous determination of glucose, fructose and lactose in food samples using a continuous‐flow chemiluminescence method with the aid of artificial neural networks
Authors: Li Baoxin , He Yuezhen 
Published: April 2007

AbstractIn this study, a simple continuous‐flow chemiluminescence (CL) system was developed for simultaneous determination of glucose, fructose and lactose in ternary mixtures of reducing sugars without previous separation. This method was based on the different kinetics of the individual sugars in the oxidation reaction with potassium ferricyanide. The known luminol–K3Fe(CN)6 CL system was used to measure the kinetic data of the system. The CL intensity was measured and recorded every second from 1 to 300 s. The data obtained were processed chemometrically using an artificial neural network. The relative standard errors of prediction for three analytes were <5%. The proposed method was successfully applied to the simultaneous determination of the three sugars in some food samples. Copyright © 2007 John Wiley & Sons, Ltd.
A new sensitive flow‐injection chemiluminescence method for the determination of H2‐receptor antagonists
Authors: Tang Yu‐Hai , Wang Nan‐Nan , Xiong Xun‐Yu , Xiong Feng‐Mei , Sun Si‐Juan 
Published: April 2007

AbstractBased on the chemiluminescence (CL) intensity generated from the potassium ferricyanide [K3Fe(CN)6]–rhodamine 6G system in sodium hydroxide (NaOH) medium, a new sensitive flow‐injection chemiluminescence (FI–CL) method has been developed, validated and applied for the determination of three kinds of H2‐receptor antagonists: cimetidine (CIMT), ranitidine (RANT) hydrochloride and famotidine (FAMT). Under the optimum conditions, the linear range for the determination was 1.0 × 10−9–7.0 × 10−5 g/ml for CIMT, 1.0 × 10−9–5.0 × 10−5 g/mL for RANT hydrochloride and 5.0 × 10−9–7.0 × 10−5 g/mL for FAMT. During 11 repeated measurements of 1.0 × 10−6 g/mL sample solutions, the relative standard deviations (RSDs) were all <5%. The detection limit was 8.56 × 10−10 g/mL for CIMT, 8.69 × 10−10 g/mL for RANT hydrochloride and 2.35 × 10−9 g/mL for FAMT (S:N = 3). This method has been successfully implemented for the analysis of H2‐receptor antagonists in pharmaceuticals. Copyright © 2007 John Wiley & Sons, Ltd.
H4 histone tail mediated DNA–DNA interaction and effects on DNA structure, flexibility, and counterion binding. A molecular dynamics study
Authors: Korolev Nikolay , Nordenskiöld Lars 
Published: April 2007

AbstractAll‐atom molecular dynamics (MD) simulations were performed during 30–45 ns for a system of three identical DNA 22‐mers, 14 short fragments of the charged H4 histone tail peptide fragment (amino acids 5–12, KGGKGLGK) with K+ counterions, and explicit water. The simulation setup mimics the crowded conditions of DNA in eukaryotic chromatin. To assess the influence of tail fragments on DNA structure and dynamics, a “control” 20 ns MD simulation was carried for a system with the same DNA and water content but in the absence of oligopeptides. Results of DNA interaction with the histone tail fragments, K+, and water is presented. DNA structure and dynamics and its interplay with the histone tail fragments binding are described. The charged side chains of the lysines play a major role in mediating DNA–DNA attraction by forming bridges and coordinating to phosphate groups and electronegative sites in the minor groove. Binding of all species to DNA is dynamic. Some of the tail fragments while being flexible and mobile in each of its functional groups remain associated near certain locations of the DNA oligomer. The present work allows capturing typical features of the histone tail‐counterion‐DNA structure, interaction, and dynamics. © 2007 Wiley Periodicals, Inc. Biopolymers 86: 409–423, 2007.This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com