bluuebunny/crossref_metadata_2025 huggingface dataset:
Nonparametric evaluation of heritability by intra‐twin differences of mono‐ and dicygotic twins
Authors: Von Eye A. , Lienert G. A.
Published: May 2007

Starting from intratwin differences x – x of two cotwins X and X in a specified trait (e.g. IQ) the following prediction was made from heredity assumption: intratwin differences will be larger in dizygotic than in monozygotic twins and will, from theoretical reasons, not be distributed normally. Therefore nonparametric testing is suggested either by U‐test or by median‐test depending on whether the differences differ in dispersion. Additionally descriptive measures of heritability were derived from the respective test statistics in such a way as to correspond to parametric heritability coefficients.
On using cluster‐analysis and multidimensional scaling for describing animal movements and bird territories
Authors: Morgan Byron J. T. , North Philip M.
Published: May 2007

Two examples are given of how multivariate analysis techniques can be used to describe bird territories and animal home‐ranges, and consequently also of how observations on fauna can reveal details of the underlying physical features.
The statistical analysis of the differential blood count
Authors: Unkelbach H. D.
Published: May 2007

The differential blood count obtained by unbiased sampling mathematically follows a multinomial distribution. The variation between individuals can be formalized by a mixing distribution of the parameters of the multinomial distribution. By DIRICHLET‐distributions used as mixing distributions the main phenomena of the observed data can be described, and they are useful in estimating and testing treatment effects. If the correlation between the different types of leucocytes is taken into account in an appropriate manner, univariate test procedures can be applied also.
Two auxiliary variates in ratio method of estimation
Authors: Agarwal S. K.
Published: May 2007

A ratio type estimator using two auxiliary variates has been proposed and conditions are obtained to choose between proposed estimator and OLKIN'S (1958) estimator using two auxiliary variates.
Micro and macro bayesian estimation of population distributions
Authors: Tziafetas George
Published: May 2007

A BAYESian probability model is described to estimate population distributions when micro or macro data about the migration of the population are available. Applying the procedure to the statistical data for two groups of 5 regions in the BRD, the macro Bayesian estimators lead to a projection of the population distributions which has a better fit than the calculated with micro Bayesian estimators. This is a basic result with a great advantage because it is possible to predict population distributions selecting only macro sample data.
Some correlation optimization problems of econometrics, statistics and psychology
Authors: Scobey P. , Kabe D. G.
Published: May 2007

Some results of conditional expectation minimization theory and canonical correlations theory are used to give a unified approach to the derivation of several known results of correlation maximization theory involving prediction of one vector variate by using linear functions of another correlated vector variate. The present unified approach is more direct and straight‐forward than the varied and different methods used by several authors to study population linear relationships between two vector variables within the framework of canonical correlation theory. The basis of our unified approach is the single underlying principle of correlation maximization.
A multivariate generalization of the FRIEDMAN rank test with application to a problem in molecular biology
Authors: Koziol J. A. , Smith C. I.
Published: May 2007

A series of experiments was recently undertaken at the National Institutes of Health to ascertain whether tRNA populations are determined by or adapted to the major proteins synthesized by tumor cells. Dissimilarity indices between chromatographic profiles of animoacyl‐tRNAs from 11 mouse plasmacytomas and from normal adult mouse liver and brain were calculated and then compared using a multivariate generalization of the FRIEDMAN rank test. This test is described herein, and its use is illustrated with data from the experiments.
Matched pairs in factorial experiments with binary data
Authors: Cox M. A. A. , Plackett R. L.
Published: May 2007

Two more models are proposed for the analysis of matched pairs in factorial experiments with binary data. They are applied to two‐period crossover designs. Estimation and test procedures are derived both approximately and by maximizing likelihoods. Comparisons are made with previous methods of analysis and between the models proposed.
Analyses of multivariately determined community matrices using cluster analysis and multidimensional scaling
Authors: Whitmore R. C. , Harner E. J.
Published: May 2007

Linear discriminant analysis was used to compute the p‐variate MACARTHUR‐LEVINS and Density Overlap measures of niche overlap between all pairs of 24 passerine bird species. The overlap values for the species pairs were then organized into a community matrix for each approach. The relationships inherent in the community matrices were structured by cluster analysis and non‐metric multidimensional scaling.

Cluster analysis identified the highly related species groups whereas multidimensional scaling demonstrated community wide relationships. In particular, the scaling approach clearly delineated shrub density and ground cover gradients.
Testing transition rates in generalized binomial models
Authors: Stucky W. , Unkelbach H. D.
Published: May 2007

In toxicological experiments the type II error is of important interest, but it is seldom discussed. For certain experiments like those in reproduction toxicology this paper gives some ideas to calculate it analytically. The basis is a generalized binomial model describing transition processes in experimental units. Each experimental unit contains a set of × members which develop from one to another specified state with some probability P. This transition probability P is allowed to vary from one experimental unit to the other; there is no restriction on the distribution of P and X, nor is P assumed to be independent of the total number × in contrast to the commonly used models. The model is extended to describe the treatment of an experimental unit, which permits to separate the treatment effect from the spontaneous development. This allows to investigate the power of some statistical tests for calculating sample sizes and for comparing different experimental designs.
Comparing treatment‐induced changes for k independent samples of paired observations
Authors: Lienert G. A. , Marascuilo L. A.
Published: May 2007

In a recent paper, MARASCUILO [19] has provided an asymptotic solution to the important question on how to test for differences in change parameters when paired observation of binary type (+, ‐) have been made on two or more independent samples of individuals.

In this article, an alternative approach is presented implying asymptotic as well as exact tests for changes. They are based on pre‐post test designs from clinical research and allow for controlled evaluation of one treatment modality as well as for comparing 2 or more than 2 treatment modalities. The rationale of the tests is based on McNEMARS [21] test for paired binary observations in one, two, or k samples.
Simultaneous sign tests for marginal homogeneity of square contingency tables
Authors: Lehmacher W.
Published: May 2007

For testing the nullhypothesis of marginal homogeneity of 1x1‐contingency tables it is proposed to perform I simultaneous sign tests and to combine them according to the BONFFERRONI or the ŠINáK inequality.
Correlation between qualitatively distributed predicting variables and chemical terms in acridine derivatives using principal component analysis
Authors: Mager Peter P.
Published: May 2007

When biological variables are not continuously distributed, the multiple and multivariate regression analysis cannot be used to correlate these variables against chemical regressors. As the employment of discriminant analysis requires the homogeneity of dispersion matrices and, that nhp where nh= degree of freedom of hypothesis, p =number of chemical terms, the reliability and validity of this method is highly questionable here. An alternative method is based on the principal component analysis where multicategory variables of drug responses can be classified into measures of inactive, slightly active, sufficiently active, and highly active drugs, for instance. The rules for classification are based on biological sources that can be expressed by chemical terms, too. An example adapted from antitumor action of acridine derivatives shows the working technique.
Mathematical methods for the acquisition of changes in vecps
Authors: Wernecke K.‐D. , Bohne B.‐D. , Ulrich W. D.
Published: May 2007

Procedures such as principal component analysis, autocorrelation and cross‐correlation, Fourier analysis, Wiener filtering, which have been used so far for the mathematical analysis of VECP mainly serve purpose of quantization and frequency analysis of signals and the evaluation of their intraindividual and interindividual variability. Although some of the above methods are also employed for the differentiation of VECPs, it seems that methods of primarily comparative character are better suited for the classification of different signal forms. This paper reports on results obtained by multivariate analysis of variance.
On Affine α‐Resolvability of a Singular Group Divisible Design
Authors: Shah S. M. , Kabe D. G.
Published: May 2007

A necessary and sufficient condition for an α‐resolvable singular group divisible design to be affine is derived here.
Optimal Split‐plot Designs for a Mixed Model
Authors: Roebruck P.
Published: May 2007

Exact tests are given, for the usual hypotheses on split‐plot models with random blocks and fixed treatment effects, considering different numbers of blocks for each level of whole‐plot treatment and assuming normally distributed observations. U‐ and D‐optimal designs are considered with respect to the tests of main effects and interactions as well as to estimation of parameters.
A Simple Construction Procedure for Eesolvable Incomplete Block Designs for any Number of Treatments
Authors: Khare Meena , Federer W. T.
Published: May 2007

A simple, straightforward procedure, which requires no special tables or generators, is presented for constructing resolvable incomplete block designs for v=pk, v=p2k, …, treatments, for k≥p, in incomplete blocks of size k. Also, it is shown, how to obtain incomplete block designs for any v in blocks of size k and k+1. The procedure allows construction of balanced incomplete block designs for p = k a prime number. For p = n not a prime number, incomplete block designs can be obtained by the procedure, but are not balanced. However, for ps being the smallest prime factor of n, ps + 1 for v = n2, ps2+ ps + 1 for v = n3, …, arrangements can be obtained for which the occurrence of any treatment pair in the blocks is either zero or one. This is called a zero‐one concurrence design. Procedures are described for obtaining additional zero‐one concurrence arrangements. It is shown that the efficiency of these designs is maximum. Both intra‐block and inter‐block analyses are described.
A Class of Ratio‐Cum‐Product‐Type Estimator
Authors: Sisodia B. V. S. , Dwivedi V. K.
Published: May 2007

The problem of estimating the population mean using an auxiliary information has been dealt with in literature quite extensively. Ratio, product, linear regression and ratio‐type estimators are well known. A class of ratio‐cum‐product‐type estimator is proposed in this paper. Its bias and variance to the first order of approximation are obtained. For an appropriate weight ‘a’ and good range of α‐values, it is found that the proposed estimator is superior than a set of estimators (i.e., sample mean, usual ratio and product estimators, SRIVASTAVA's (1967) estimator, CHAKRABARTY's (1979) estimator and a product‐type estimator) which are, in fact, the particular cases of it. At optimum value of α, the proposed estimator is as efficient as linear regression estimator.
Goodness of Fit of Discriminant Functions from the Vector Space of Fixed Variates
Authors: Kabe D. G.
Published: May 2007

Alternative proofs of some of KSHIRSAGAR's (1971) results on testing discriminant functions or canonical variables in the vector space of fixed variates are given. These results are derived in terms of the original variates unlike KSHIRSAGAR (1971) who derives the results by using random orthogonal transformations and triangular decompositions of the original matrix variates.
Multiple Decrement Analysis with Dependent Risks
Authors: Nour EL‐Sayed E.
Published: May 2007

In a competing risks problem where a well‐defined population is exposed simultaneously to several causes of death, interest has centered on the estimation of the probability of death from a given cause when one or more other causes have been eliminated. A basic component of all available procedures for estimating these probabilities is the assumption that the several causes of death act independently—an unrealistic assumption in the context of human and animal populations.

This article considers the estimation of these probabilities assuming the existence ofinterdependencies among the various causes of death. A general formula is derived based on a given set of crude probabilities of death as well as the characteristics of the joint distribution of random variables indicating death from the various causes. This formula identifies alternative assumptions, less restrictive than that of independent risks, which may he used for estimation purposes.
Analysis of Detection Processes for Breast Cancer
Authors: Tallis G. M. , O'neill T. J.
Published: May 2007

Most existing records of detection processes for breast cancer are in the form of cancer registries or are results of large clinical trials. Statistical modelling can be applied to these data sets to study various properties of breast cancer. In particular we estimate the probability of cure given the size of the tumour at detection, the distribution of tumour growth rates and the distribution of the size of the tumour at detection. There has been a strong recent interest in early detection methods. These consist of giving regular examinations, called screenings. The effect of screening design on the probability of cure is considered. The results of an existing screening trial are used to derive another estimate of the tumour growth rate distribution which agrees well both with our earlier estimate and the most widely used empirical estimate in the literature. The calculation of lead time, which is the time gained in detection when screenings are given, is also discussed.
On Two Measures of Unbalancedness in a One‐Way Model and Their Relation to Efficiency
Authors: Ahrens H. , Pincus R.
Published: May 2007

This paper discusses two measures of unbalancedness in a one‐way model and shows that for a given statistical procedure they may serve as measures of efficiency of a design. They also allow to compare for example estimation methods for variance components in designs with a fixed level of unbalancedness.
The Estimation of a Multivariate Fitness Function from Several Samples Taken from a Population
Authors: Manly B. F. J.
Published: May 2007

The situation is considered where the multivariate distribution of certain variablesX1, X2, …,Xpis changing with time in a population because natural selection related to theX's is taking place. It is assumed that random samples taken from the population at timest1,t2, …,tsare available and it is desirable to estimate the fitness functionwt(x1,x2,…,xp) which shows how the number of individuals withXi=xi,i= 1, 2, …,pat timetis related to the number of individuals with the sameXvalues at time zero.

Tests for population changes are discussed and indices of the selection on the population dispersion and the population mean are proposed. The situation with a multivariate normal distribution is considered as a special case. A maximum likelihood method that can be applied with any form of population distribution is proposed for estimatingwt.

The methods discussed in the paper are illustrated with data on four dimensions of male Egyptian skulls covering a time span from about 4500 B.C. to about 300 A.D. In this case there seems to have been very little selection on the population dispersion but considerable selection on means.
Optimal Allocation, Precision, and Significance Tests
Authors: Finney D. J.
Published: May 2007

HORN (1979) queried the recommended ratio 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 rule was originally stated for maximizing the precision of estimates, and not for optimizing any aspect of significance tests. Although in applied statistics, significance tests are usually of far less importance, it is interesting (but scarcely surprising) that the same rule optimizes power and one or two related characteristics.
Zur „Genauigkeit”︁ bei J. G. Mendel
Authors: Hellmich K.
Published: May 2007

When taking into account J. G. MENDEL's observed frequencies and comparing them with those noted down by BATESON, CORRENS and DARBISHIRE no „striking”︁ preciseness in accordance with the statement made by F. WELLING is to be noticed statistically. By means of the four‐field table measure K speculations as to a „too precise”︁ indication of frequencies are to be refuted in an easy way.
A Remark on the Mathematical Motivation of the Second Law of Thermodynamics from a Biological Point of View
Authors: Leuschner D.
Published: May 2007

In connection with biological systems characterized essentially by substance exchange with environment a statistical motivation of the second law of thermodynamics could be given.
On the Theory for RYANS Universal Multiple Comparison Procedure with Treatment of Ties in the Ranks of Samples
Authors: Horn M.
Published: May 2007

The proposal of RYAN (1960) for multiple comparison procedures has not become well known despite of its universal applicability. Only his idea of adjusted levels has been used in a modified manner, cf. EINOT and GABRIEL (1975), WELSCH (1977), RAMSEY (1978). This article re‐introduces the procedure and demonstrates its broad applicability also as a nonparametric method. Above all an exact mathematical foundation is aspired. The case of ties in the ranks of samples has been taken into consideration.
Log‐linear Models for Polytomous Data
Authors: Formann Anton K.
Published: May 2007

The present study discusses two variants of linear logistic models for polytomous variables for „unordered”︁ and for „ordered”︁ categories (polydimensional and one‐dimensional model). The ML‐estimation equations and the possibilities to test the validity of the model are given for both. A test for goodness‐of‐fit (external validity) and a test for equality of the parameter estimates for split data (interval validity) are suggested. In addition, statistical tests for the significance of individual parameters on the basis of the information matrix and likelihood ratio tests for one or more parameters are described. The presentation is completed by an empirical example from the area of audiology.
Methods for Checking Assumptions in Regression Models
Authors: Bandemer H.
Published: May 2007

The usual assumptions in regression analysis are: The setup is true; the random errors are uncorre‐lated (and normally distributed); and the data contain no outliers. Reasoning known recommendations to check these assumptions by inspection of the residuals new proposals are discussed and illustrated by an example.
Bivariate POISSON Binomial Distributions
Authors: Charalambides Ch. A. , Papageorgiou H.
Published: May 2007

Three bivariate generalizations of the POISSON binomial distribution are introduced. The probabilities, moments, conditional distributions and regression functions for these distributions are obtained in terms of bipartitional polynomials. Recurrences for the probabilities and moments are also given. Parameter estimators are derived using the methods of moments and zero frequencies and the three distributions are fitted to some ecological data.
On Maximum Likelihood Solutions for Exponential Survival Models
Authors: Beck G. J. , Chiang C. L.
Published: May 2007

Stochastic survival models which adjust for covariate information have been developed by BECK (1979). These models can include one or two living states and several competing death states. The transitions between states are assumed irreversible and the transition intensity functions are assumed to be independent of time but dependent upon the covariates. This paper presents explicit solutions of the maximum likelihood equations for such models when there are only one or two dichotomous covariates. Two applications of these models are discussed where survival in two or four groups are compared.
Über Gausssche MARKOV‐Prozesse als Wachstumsmodelle
Authors: Berg L.
Published: May 2007

To find appropriate models for growth processes we determine firstly all non‐singular Gaussian Markov processes and give later on two simple specializations for them. The parameters appearing in this context are estimated by the maximum likelihood principle, whereas the numerical calculation of them is done by help of the Gauss‐Newton algorithm. Final remarks concern the evaluation of a start vector for this algorithm with respect to the GOMPERTZ‐function and the introduction of a simple simulation model.
On the Convergence of an Algorithm of Jones
Authors: Catchpole E. A.
Published: May 2007

Pearce (1976) proposed the use of the variance matrix for design block experiments. Jones (1976) gave an iterative formula for, but stated that the iteration failed to converge for some block designs. We derive necessary and sufficient conditions for the convergence of JONES' iteration. We also note that a simple modification to JONES' iteration will ensure its convergence.
Explicite Formulae of Exact Tests in Mixed Balanced ANOVA‐models
Authors: Seifert B.
Published: May 2007

As an alternative to SATTERTHWAITE's approximative test strongly unbiased tests of BARTLETT‐SCHEFFÉ type are considered to test hypotheses about fixed and random effects in mixed and random ANOVA‐models with equal cell frequencies. Explicite formulae are given to test hypotheses in the usual two‐ and three‐way classifications and the four‐way cross‐classification. These formulae also can be used in the multivariate case.
Product Cum Difference Method of Estimation Using two Auxiliary Variables
Authors: Singh R. Karan , Ray S. K.
Published: May 2007

Product method of estimation (MURTHY, 1964) using supplementary information on an auxiliary variable having high negative correlation with the main variable under our study, is well known. In this paper, we propose product‐cum‐difference method of estimation for the population total and the product of population parameters when supplementary information is available on two auxiliary variables. A comparison of product‐cum‐difference method of estimation with the usual product method of estimation using single auxiliary character and the estimators by SINGH (1965) for the estimation of product of population parameters has been made along with an empirical study.
The Classical Assortative Mating Process when more than one Continuous Characteristic is Considered
Authors: Wilson Susan R.
Published: May 2007

In this article we give a general proof for the existence of the equilibrium position for the joint phenotypic distribution of several continuous characteristics, in a population which reproduces assortatively, and wherein generations are overlapping. This model is a more realistic one for human populations, compared with models arising from consideration of a single characteristic. By placing realistic conditions on the assortation process in the equilibrium position it is found that the consequences are even less realistic and less satisfactory compared with conclusions from single (continuous) characteristic models involving assortative mating. This suggests that a different approach to modelling the assortation process may be required, and this is discussed alsewhere (WILSON, 1981).
On a restricted occupancy model and its applications
Authors: Charalambides Ch. A.
Published: May 2007

With the multivariate hypergeometric distribution as a background certain occupancy distributions useful in practical applications are derived. More specifically it is assumed that a sample ofnindividuals is drawn from a population consisting ofmtypes withrindividuals in each type, (i) without replacement and (ii) by returning the selected individual in the population and with it another individual of the same type. The distributions of the numberZof distinct types observed in the sample are obtained in both cases in terms of the numbers. Assuming, in addition to themequiprobable types of individuals, the existence of a control type, say, withsindividuals, the joint distribution of the numberUof distinct types observed in the sample and the numberVof individuals of the control type present in the sample is obtained in terms of the numbersC(n, k, r) and the marginal distribution ofUin terms of the Gould‐Hopper numbers. Using these distributions minimum variance unbiased estimators of the numbermof types are derived. Moreover small sample tests based on the zero frequency are constructed.
A specification of numerical taxonomy: Thermodynamical taxonomy
Authors: Leuschner D.
Published: May 2007

Thermodynamic taxonomy (ThT) is established from both a theoretical and pragmatical point of view. An application of thermodynamic taxonomy is given.
On an Unbiased Variance Estimator for the WILCOXON‐MANN‐WHITNEY‐Statistic Based on Ranks
Authors: Hilgers R.
Published: May 2007

For some applications of the WILCOXON‐MANN‐WHITNEY‐statistic its variance has to be estimated. So e.g. for the test of POTTHOFF (1963) to detect differences in medians of two symmetric distributions as well as for the computation of approximate, confidence bounds for the probability P(X1 ≥ X2), cf. GOVINDARAJULU (1968). In the present paper an easy to compute variance estimator is proposed which as only information uses the ranks of the data with the additional property that it is unbiased for the finite variance. Because of its invariance under any monotone transformation of the data its applicability is not confined to quantitative data. The estimator may be applied to ordinal data just as well. Some properties are discussed and a numerical example is given.
On HÜHN's Notion of Optimal Sample Size in the χ2 Goodness of Fit Test
Authors: Rayner J. C. W. , Best D. J.
Published: May 2007

Hühn's notion of optimal sample size for the χ2 goodness of fit test is discussed. It involves minimising the achievable level of the test subject to a given nominal level. This ignores the power of the competing tests and can lead to an ‘optimal’ test that is uniformly less powerful than all the competing tests considered.
Note on a Test for Trend in Binomial Proportions Using Ranks
Authors: Bennett B. M.
Published: May 2007

For a 2xk contingency table when all the k groups fall into a natural order and for which a sequence of k values × may be assigned, ARMITAGE (1955) has suggested a X2(1) test statistic for the hypothesis Ht of a trend in the proportions; This note considers a statistic for Ht based on midrank values for the binary observations. It is shown that the proposed rank‐order test for Ht coincides with that of ARMITAGE (1955).
On G‐Efficiency of some Second Order Rotatable Designs
Authors: Mitra R. K.
Published: May 2007

The effect of adding central points to a given design on theG‐efficiency has been examined for certain classes of second order rotatable designs.
Stability Investigations of Linearized Systems with Random Structure
Authors: Rademacher P.
Published: May 2007

The relationship between complexity and stability of linearized systems, being characterized by structural parameters like dimension and connectance and interaction strength are investigated by computing relative frequencies of stability. The results are compared with those of other authors. Additionally systems with a special cyclic subsystem structure are investigated. Comparing the stability properties for structured and unstructered systems no increase in stability can be stated if systems are structures in the supposed way.
Application of Fast Fourier Transform in Electroencephalography
Authors: Matthies H. K. , Brödemann R.
Published: May 2007

Today the Fourier Transform is also used in the analysis of biological time series with periodical parts. For N = 2M EEG sampling values the Fast Fourier Transform algorithm of COOLEY and TUKEY is applicable. For this a FORTRAN IV program EEG‐FFT has been developed for computation of power spectrum.

At the data processing equipment EC 1040 the CPU‐time for 210 = 1024 EEG sampling values is smaller than 1.5 s.

The FORTRAN IV program can be applied both in offline and online data processing.
Scale‐independent non‐parametric multivariate tolerance regions and their application in medicine
Authors: Abt K.
Published: May 2007

Based on the principles introduced by TUKEY and FRASER, a method is proposed to construct non‐parametric multivariate tolerance regions of irregular multiplanar shape. Contrary to the regions of corresponding shape as constructed by Tukey and Fraser, the tolerance regions constructed according to the proposed method can be shown to be invariant to linear scale transformations. In medical applications, where the concept of multivariate tolerance regions can be used to define “normal” regions for p ≦ 2 variables with measuring units generally differing from each other, the quality of scale‐independency of the regions is essential. With reference to the method proposed, sample size determination and some important aspects of the use of multivariate tolerance regions are discussed.
On Kernel Methods of Estimating Marginal Radial and Angular Probability Density Functions
Authors: Byth Karen
Published: May 2007

Spatial point patterns which possess a natural origin are considered. Two ways of estimating the marginal radial and angular probability density functions associated with the stochastic process underlying such a pattern are presented. These methods are based on one and two‐dimensional kernel functions respectively. The angular density estimate can be used to detect angular trend and to test for angular uniformity within a particular sector about the origin. The two methods of estimation produce essentially the same results. That based on the one‐dimensional kernel is recommended because it is computationally simpler.
Bioassay Approach to Prescribe Safe‐limits of Exposure to Non Ionizing Radiation in Ecosystems
Authors: Neelakantaswamy P. S. , Meng Fong Ah
Published: May 2007

A biological assay that quantifies hazardous response in living matter to an electromagnetic stimulus, is evolved. Considering the various susceptible aspects of physio‐anatomical systems constituting a living subject, a dominance criterion to determine an optimum all‐or‐none response limit of exposure to electromagnetic pollutions is established. Based on the statistics of proneness and susceptibility of discrete physio‐anatomical parts of living systems (biotic components) to polluting radiations (abiotic environment), the stochastic nature of damage involved is considered to formulate a quantal index which specifies a “safe” intensity‐level of electromagnetic radiation to which living systems can be exposed without encountering any deleterious effects. The locations of vulnerable parts which are affected by radiation are identified through random mosaic modeling of a test subject. Using this model, a susceptance priority sequence of biotic components is constructed. This sequence is then terminated at a point of weightage proportional to the diversity of victim population. The biotic species falling within this limit of truncation are subsequently studied to assay the tolerance (optimum lethal dose) of the test subject to the radiation in question. The possibility of simulating the entire ecological system under consideration by means of a microprocessor is suggested.
Zur Bestimmung des Wanderungsprozesses
Authors: Tziafetas G. N.
Published: May 2007

In this paper we analyse the migration process in connection with the birth and death process. We assume that the populations are distributed spatially and are subject to birth, death and migration to or from neighbouring populations. Furthermore, we distinguish between populations with infinite and finite number of colonies. By this way we calculate the cumulant of first order.

First this problem was studied by BAILEY and ADKE for time‐dependent rates. Similarly PURI has specialized the problem for right migration (vij = 0 for i ≢ j). Finally RENSHAW had the same result with other procedures.
Minimum Variance Unbiased Estimation in a Bivariate Modified Power Series Distribution
Authors: Shoukri M. M.
Published: May 2007

The functional form of the class of Bivariate Modified Power Series Distributions is considered. The probabilities are functions of two unknown parameters ϑ1 and ϑ2. The necessary and sufficient conditions for the existence of a minimum variance unbiased estimator for a parametric function of ϑ1 and ϑ2 are given.
Likelihood Under the Mixed Model for Quantitative Traits
Authors: Simpson J. M. , McGilchrist C. A.
Published: May 2007

Mathematical details of obtaining the likelihood functions for testing hypotheses under the mixed model for quantitative traits are given. Since families are assumed to be chosen by the value of the trait of a particular family member, conditional distributions are required. Algorithms for efficient computation of the likelihood are given.
The Use of a Symbol Processing Computer Language in Point Estimation of Parameters and in Construction of Confidence Intervals
Authors: Quednau H. D.
Published: May 2007

This paper presents a method to generate automatically computer programs which are necessary for parameter estimation, hypothesis tests and construction of confidence intervals by the maximum likelihood method. The spectral or density function of the random variable is arbitrary, but must be known and given in closed form. The programming language used is the symbol processing language LIBAFORM, whose statements are interpreted by a package of LISP‐routines. The application of the method is illustrated by the analysis of a linear model whose residuals follow a logarithmic F‐distribution, and the analysis of a dose‐response curve.
The Exact Evaluation of 2‐way Cross‐classifications: An Algorithmic Solution
Authors: Kannemann Klaus
Published: May 2007

An algorithm is presented which permits the exact evaluation of sparse cross‐classifications and contingency tables. It may be used to compute the exact point and cumulative probabilities of observed values of the X2‐like test statistic, or even of the observed tables themselves. For sparser cases, it may also be used to generate part or all of the exact distributions. As a corollary, an operational solution is presented to the enumeration problem of rectangular integer matrices with arbitrarily fixed row and column sums. Exact results obtained with the algorithm accompany this presentation, giving, further support to the recommendation that the Gamma distribution be preferred to the Chi‐square in sparse cases.
A FORTRAN Program for the KASTENBAUM‐BOWMAN Test
Authors: Würgler F. E. , Berchtold W.
Published: May 2007

The KASTEITBAUM‐BOWMAN test allows the determination of the significance of a mutation frequency. A simple FORTRAN program for the KASTENBAUM‐BOWMAN test is given. The subroutines may be incorporated easily into larger programs and allow to calculate the exact P value for the test.
The Statistical Significance of Mutation Frequencies
Authors: Würgler F. F. , Graf U.
Published: May 2007

TRAUT has proposed a method for determining the statistical significance between a mutation frequency observed after treatment with a potential mutagen and a control frequency. The method is developed further by us for an easier practical use. A table for the minimal sample size in the region of interest for the sex‐linked recessive lethal test in Drosophila melanogaster has been calculated.

TRACT'S test is compared with FISHER'S exact test and the KASTENBAUM‐BOWMAN test. TRAUT'S test turns out to be more sensitive than the other tests. This observation strongly supports TRAUT'S conclusion that his test should only be used if very accurate determinations of the spontaneous frequencies are available.
Nonparametric Tests for Slope in Linear Regression Problems
Authors: Gore A. P. , Rao K. S. Madhava
Published: May 2007

In this paper some new, exactly distribution‐free tests are offered for the hypothesis about the slope parameter in one‐sample, two‐sample, and several‐sample simple linear regression problems. Asymptotic relative efficiencies of these test procedures are also studied.
The Sizes of Spheres from Profiles in a Thin Slice I. Opaque Spheres
Authors: Coleman Rodney
Published: May 2007

Thin slices through specimens are made into slides for use in microscopy. If a specimen consists of opaque spherical particles in a transparent medium, there will be seen through the slice circular profiles of particles and sections through particles. For a random slice, the size distribution of these profiles can be related to the size distribution of the population of spheres. The extensive literature dealing with this relationship is surveyed.

An important generalization of practical importance is made with the introduction of a resolution interval which excludes from observation those profiles that are too large or too small. How this affects the relationship between the profile and sphere size distributions is considered, and some special cases are used as illustrations.

In Part II (COLEMAN, 1983) the corresponding results for the case of transparent spheres in an opaque specimen are given.
A Further Problem of Interval Estimation of an Unknown Regressor in Model I of Linear Regression
Authors: Hess J. , Horn M.
Published: May 2007

For the model y = α + βx + ϵ (model I) of linear regression we dealt with in KUHNERT and HORN (1980) the determination of a confidence interval for that x0 where the expectation Ey reaches a given value y0. Here we start with realizations of random variables y (i = 1,…, m) being independent of x which are given in addition to the realizations of‐y. Now y0 denotes the unknown value of \documentclass{article}\pagestyle{empty}\begin{document}$ \mathop \sum \limits_{i = 1}^m $\end{document} ciEy and x0 the x‐value where the expectation Ey reaches that value y0. For this x0 we give a confidence interval. Applications stem from dose response assays.
A Suprasystem of Probability Distributions
Authors: Savageau M. A.
Published: May 2007

A set of differential equations is described whose solutions represent a general system of probability distribution functions. Previously reported systems of such distribution functions are special cases of this general system. The differential equations can be used to represent distribution functions and generate their related statistics in cases for which no simple formula for the distribution is known. The generality of this suprasystem of distribution functions and its potential utility are discussed.
Some Remarks on the Estimation of Mean in the Normal Population
Authors: Chaubey Y. P. , Dwivedi T. D.
Published: May 2007

This paper generalizes the estimator proposed by Searles (1964) and further studied by SRIVASTAVA (1980) and gives some expressions for the first two moments and an integral representation for the αth raw moment. The latter is found suitable for computational purposes. Some points in SRIVASTAVA'S (1980) paper are also clarified. Efficiencies of 3 estimators belonging to this class are analyzed with respect to the usual sample mean.
The Estimation of Variance Components in a special Class of Phase‐Confounded Designs
Authors: El‐Beshir Z. A.
Published: May 2007

This paper considers the estimation of variance components for a special subclass of Phase‐confounded designs. It is shown that if the balance existing in the design is utilized relatively simple expressions for the solutions of the normal equations and the relevant sums of squares can be obtained.
On the Equivalence of the Information‐Theoretic Transmission‐Measure to the Common χ2 Statistic
Authors: von Eye Alexander
Published: May 2007

The results of a simulation study are presented in which the χ2‐and the information theoretic approach to association measurement were compared to one another. It could be shown that neither the maximal values nor the minimal values obtainable for a given sample size coincide in all cases. The underlying association concepts are defined; implications are discussed.
An Inhomogeneous Markov Model to Fit the Migration Process
Authors: Tziafetas George N.
Published: May 2007

In this paper we study the migration process considering an inhomogeneous Markov model. This is a certain condition to investigate age‐dependent population distributions, where the transition probabilities are not constant. We consider also a death process for a population alive in a region at age t and, as a result of this, combined transition probabilities between the states of the concerning Markov chain. The model has non‐stationary distribution for t →∞, because the condition of ergodicity does not hold.
Comparing Two Samples of Response Curves by Nonparamètric Tests of Predicted Order
Authors: Lienert G. A. , Munzert R.
Published: May 2007

Starting from MOSTELLER'S (1955) one‐sample test of predicted order, some two‐sample versions are proposed for comparing nonparametrically a treatment group (m response curves) with a control group (n response curves) as to a predicted shape represented by a specified rank order. The tests are applied to two groups of learning curves.
On the Probability of a Negative Estimator of Heteroscedasticity in the Random Coefficient Model
Authors: Srivastava V. K. , Raj Baldev
Published: May 2007

In the estimation of a linear regression model with random coefficients, sometimes negative estimates of variances of random coefficients are obtained–an undesirable feature. In this paper we have obtained the asymptotic bounds of the probability of obtaining negative estimators. A simple illustration is also provided for the purpose.
Cylindrically Rotatable Designs of Type 3: Further Considerations
Authors: Huda S.
Published: May 2007

The cylindrically rotatable designs of type 3 are generalised to consider the factors split up into any number of groups. The conditions which must be satisfied by such a design are derived from the moment generating function of the design. A method of construction of second‐order cylindrically rotatable designs of type 3 with three or more groups of factors is provided.
A New Variant for Mathematical Analysis of Pulse Cytophotometric Data
Authors: Weidhase R. A. , Schneeweiss B. , Müller E.
Published: May 2007

The staining of DNA by specific fluorochromes provides a suitable method of receiving histograms in a short time by means of pulse cytometry. They represent the proliferative structure of cell populations at a high degree of statistical security.

A method for quantitative determination of cell cycle phases (G1‐, S‐ and G2 + M‐phase) is presented which includes the fraction of cell debris in the calculation procedure. The advantages of this method are the elimination of overlapping between the fraction of debris and cell cycle phases and the quantitative determination of the fraction of cell debris offers the opportunity to get information on cytolytic potencies. Apart from the calculation of the various cell cycle phases the method provides criteria on the adaptation of mathematical analysis to primary data.
On Errors of Measurement
Authors: Jílek M.
Published: May 2007

When any process of measuring is considered, one of the basic questions is how to assess the precision of measurement methods and/or instruments. In this paper, this question is formulated and solved as a problem of tolerance regions for absolute and relative normaly distributed errors of measurements.
Powers of Chords for Convex Sets
Authors: Voss K.
Published: May 2007

The powers of chords Sn of planar convex sets are generally known only for n = 0, 1, and 3. They depend on the special shape of the convex set. Here integral formulas for the equilateral triangle, the square, and the ellipse are given. Furthermore, using area moments of the convex sets, S5 and S7 are derived in general form. For the 3‐dimensional space S6 and S8 are given.
On Double Sampling Ratio‐Cum‐Product‐Type Estimator with Independent Samples
Authors: Sisodia B. V. S. , Dwivedi V. K.
Published: May 2007

There are two cases in double sampling; case(i) when the second sample is a sub‐sample from preliminary large sample, and case(ii) when the second sample is not a sub‐sample from the preliminary large sample. Recently SISODIA and DWIVEDI (1981) proposed a ratio cum product‐type estimator in double sampling in which they have studied the properties of this estimator under case (i). In this paper, we have made an attempt to study the properties of the same estimator under case (ii). It is found that the estimator is superior than double sampling linear regression estimator, usual ratio estimator, product estimator and among others. The estimator is also compared with simple mean per unit for a given cost of the survey.
Characterizations of the Exponential Distribution by Local Maximum Random Variables
Authors: Ahsanullah M.
Published: May 2007

Let {Xn, n≧1} be a sequence of independent and identically distributed random variables. Suppose n(K)=min n for which Xn>Xk, with K fixed and n>K. We will characterize the exponential distribution by considering the distributional properties of Xk and Xk and Xn(k).
A Note on the Mann‐Whitney Statistic for Lehmann Alternatives
Authors: Abely U.
Published: May 2007

For the case of the LEHMANNalternatives the paper presents some new facts on the MANN‐WHITNEYstatistic and, in particular, its varianceV(p, m, n), wherep = P(xi<yi). Explicit formulas forUandVare used to prove, among other things, the following propositions: For anym, n, Vis a one‐hump function ofp, and the hump always lies in the interval (1/2(3 ‐ √5), 1/2(√5 ‐ 1)). If no restrictions are imposed onpthe boundaries of this interval are sharp. Givens = m + n, V(1/2, s/2,s/2) is maximal among all valuesV(p, m, n). The formulas allow, moreover, the improvement of the known bounds for the variance of p̌ =U/mn.
Open‐ended assignments and student responsibility
Authors: Brauner Annelie , Carey Jannette , Henriksson Marie , Sunnerhagen Maria , Ehrenborg Ewa
Published: May 2007

An inquiry‐based laboratory course was created in an effort to increase student responsibility in learning and to improve teaching in areas related to molecular medicine. Authentic medical cases with both scientific and clinical aspects formed the basis of a project‐oriented course that also included student laboratory work focused on the disease‐related proteins. Students used basic biochemical techniques to develop and test hypotheses relating their results to the clinical findings. The course also included patient demonstrations to personalize students' knowledge of case presentations, lectures on basic biochemical principles relevant to the molecular basis of the cases, and seminars by invited guests with expertise in translational medicine. Students developed proposals for future research as part of the final examination. An inquiry matrix was used to evaluate the degree of learning responsibility taken during the course. By allowing for openness in how to explore the case including choice of methods and interpretation of unexpected results, students gained confidence in their ability to solve problems, formulate and test hypotheses, and collaborate with both clinical and non‐clinical professionals.