bluuebunny/crossref_metadata_2025_split huggingface dataset:
An Alternative Approach to Modelling the Assortative Mating Process
Authors: Wilson Susan R. 
Published: May 2007

AbstractIn this article we demonstrate how the difficulties encountered from consideration of two‐sided assortation for a characteristic (or set of characteristics) in human populations can be overcome. This is achieved, essentially, by postulating a socio‐environmental variable (based on an individual's lifetime experiences) over which individuals are mating assortatively. The value an individual has on this scale determines his mean value for the characteristic under consideration. In other words, there is a relationship between the characteristic and the socioenvironmental scale. As well, individuals may be mating assortatively for the characteristic under consideration (although not necessarily). Thus we achieve assortative mating for a single characteristic as a result of mixing, simultaneously, over more than just one variable. Expansions to more ‘mixing’ scales than a single socio‐environmental variable are quite straightforward.
On Asymptotically Distribution‐Free Confidence Bounds for P (X1≥X2) Based on Samples not Necessarily Independent
Authors: Hilgers R. 
Published: May 2007

AbstractIf X1, X2, denote the random variables of measurement under two treatments then the probability P (X1 ≥ X2) is a quantity of great practical interest, especially if we consider both to be measured for the same unity. In this case the random variables cannot be assumed to be independent any longer. The following paper describes a procedure to compute approximate confidence bounds for P (X1 ≥ X2) where correlations between X1, X2 are admitted as well as between replications of the Xj. There is some relation to the FRIEDMAN‐statistic with or without repeated measurements and as a special case to the sign‐test. Application may be extended to ordinal data.
On the Modified and Inflated Discrete Distributions
Authors: Lingappaiah G. S. 
Published: May 2007

AbstractFirstly, a modified bivariate discrete distribution is considered where a set of counts are misreported as another set of counts with different modification rates. Variances and covariances are put in the closed form and for the case when all modification rates are the same, these variances and covariances are expressed as parabolic functions and they are actually evaluated for the bivariate negative binomial. Regarding the asymptotic distributions of the estimates, elements of variance‐covariance matrix are obtained. Next, a multivariate inflated discrete distribution is taken up. For the case of inflated multivariate negative binomial, Bayesian estimates of inflation as well as those of parameters are given.
Nonparametric, GINI‐like Measures of Location and Dispersion
Authors: Lienert G. A. 
Published: May 2007

AbstractGINI's nonparametric measure of dispersion, defined as the mean of (n/2) pairs of a sample of n measurements, is modified for triplets. That way a GINI‐like measure of location G* is defined as the mean of the (n/3) triplet medians, and a GINI‐like measure of dispersion is defined as the mean of the (n/3) triplet ranges. G* and g* are less sensitive to outlier measurements than are the corresponding parametric measures, arithmetic mean and standard deviation, in small samples. Applications and application‐related problems are discussed.
Methods of Discrimination Among Stochastic Models of the Negative Binomial Distribution with an Application to Medical Statistics
Authors: Rockhold F. W. , Kilpatrick S. J. 
Published: May 2007

AbstractThe Negative Binomial Distribution (NBD) can be derived from several underlying stochastic processes. For the NBD to be useful in practice as a descriptive model, it would be of interest to know which underlying process it is characterizing. In this paper, methods for discriminating among three different NBD underlying processes, proneness, linear contagion, and spells, are developed and studied. The methods are based on the characteristics of the processes and employ the theory of the bivariate NBD and waiting times. The NBD has been shown to consistently fit data on the incidence of disease. Knowledge of the underlying process generating the data is important for meaningful interpretation of such findings.
The Correlated Bivariate Inverted Beta Distribution
Authors: Lee P. A. 
Published: May 2007

AbstractThe correlated bivariate inverted beta distribution is constructed from the bivariate mixture of two independent gamma random variables whose scale parameters follow Kibble's correlated gamma distribution. Explicit expressions have been derived for the form of the joint probability density function, the joint cumulative distributive function and other statistical properties of interest. These results confirm and extend some of the conjectures of HUTCHINSON in connection with generalizations of probabilistic models of severity distribution arising from injuries sustained in two‐vehicle head on collison.
Sample Sizes in Sequential Survival Clinical Trials
Authors: Nagelkerke N. J. D. , Hart A. A. M. , Strackee J. 
Published: May 2007

AbstractIn survival clinical trials the response, i.e. (time to) death is delayed. As a result there are at any time patients that have not responded, yet. Given a stopping rule based on the number of deaths, the distribution of the total number of patients that will enter the trial is examined. Besides, a simple approximation to the expected number of patients is presented.
On a Characterization of the Exponential Distribution by Weak Homoscedasticity of Record Values
Authors: Ahsanullah M. 
Published: May 2007

AbstractA sequence {Xn, n≤1} of independent and identically distributed random values with continuous cumulative distribution function F(x) is considered. Xj is a record value of this sequence if Xj ≤ max (X1, X2, …, Xj−1). We defineL(n)=min.(j!j>L(n−1.), Xj<XL(n−1)), with L(0) = 1.Let Zn=XL(n)− XL(n−1), n ≤ 1. We will show that the conditional variance of Zn given XL(n−1)=x does not depend on × if and only if F(x) is exponential.
A Product‐Type Estimator in Double Sampling
Authors: Ray S. K. , Singh R. Karan 
Published: May 2007

AbstractThe use of ratio and product estimators, using auxiliary information, for estimating the mean of a finite population is well known. The efficiency of ratio estimator or product estimator is high depending on whether the auxiliary character is highly positively or negatively coorelated with the main character of interest. This paper proposes a product‐type estimator which is more efficient than the usual ratio and product estimators in practical situations. We consider the case of double sampling from which the single sampling results may easily be derived.
On the Bayeaian Estimation with Changing Failure Rate
Authors: Gupta R. P. , Shah S. M. 
Published: May 2007

AbstractIn certain‐life experiments it may happen that the failure rate may change after some initial period of time. Thie meane that the failure rate during certain interval of time and that of thereafter will differ significantly. Thie suggests a failure model in which one failure rate is assumed to be operative during period of time, say[0, T]. and another failure rate ie operative thereafter, that is after time T. In thie paper, Bayesian point estimates of these fnilure rates are obtained when underlying probability law law is exponential and T is known.
On the WILCOXON‐MANN‐WHITNEY‐Test as Nonparametric Analogue and Extension oft‐Test
Authors: Hilgers R. 
Published: May 2007

AbstractIn the present paper some basic aspects of the WILCOXON‐MANN‐WHITNEY‐test under various assumptions concerning the underlying distributions are studied. Starting with a formal analogy to Student'st‐test its specific sensibility is worked out and the connexion to the problem of testing differences in location is discussed in detail as well as to the model with ordered alternatives. Further a counter example is given showing that the common verbal formulation the WILCOXON‐MANN‐WHITNEY‐test being a test on ‘differences in distribution’ in general is misleading. As an example of an extended application of the WILCOXON‐MANN‐WHITNEY‐statistic the test of POTT‐HOFF(1963) on differences in medians of symmetric distributions is treated together with a discussion on suitable variance estimators to guarantee appropriate asymptotic distribution.
On Generalized Indices of Diagnostic Efficiency
Authors: Bennett B. M. 
Published: May 2007

AbstractThe usual definitions of sensitivity, specificity and predictive value of a diagnostic testTrefer only to the situation of the presence or absence of disease. There is then question of the appropriate extensions of these definitions in cases where there are more than two diagnostic categories, especially with ordered or graded responses. This paper deals with some aspects of this problem. An example with the data of BERGESONand STEINFELD(1974) on gradings of fever in children by palpation is analyzed, using the methods discussed in this paper.
Stochastically Independent Components in the Analysis of Variance
Authors: Drwięga T. 
Published: May 2007

AbstractIn this paper an analysis of a sum of squares for linear hypothesis in a fixed linear model is presented. The analysis is based on a partition of sum of squares into independent components. These components are treated as sums of squares for hypotheses implied by an overall one. In the special case components of a sum of squares are distributed with one degree of freedom each and hypotheses concern single parametric functions. In the model not of full rank the form of a sum of squares is transformed before partitioning. The case of the model for cross classification is considered in details. Next the cases of the model of full rank and the one with restrictions on parameters are discussed. The model for balanced design with unweighted restrictions on parameters is considered in details. In this case sume of squares for orthogonal contrasts are obtained from analysis of the sum of squares for hypothesis concerning main or interaction effects.
Tables of the critical values for simultaneous and sequential Bonferroni‐z‐tests
Authors: Lienert G. A. , Ludwig O. , Rockenfeller K. 
Published: May 2007

AbstractSimultaneous and sequential BONFERRONI‐tests (HOLM, 1979) are going to replace the traditional global tests (ANOVA, PEARSON‐χ2). To facilitate (sequential) BONFERRONI‐evaluation, BONFERRONI‐test limits for the normal distribution are tabulated for r = 1(1)100, 100(2)300, 300(5)800, 800(10)1600, 1600(20)3200, 3200(50)10000 tests and for some conventional alphas in one‐ and two‐sided alternatives.
Using Ranks in Parallel Line Assays
Authors: Pettitt A. N. 
Published: May 2007

AbstractAn approximation to the likelihood of a sample, based on the ranks of the observations only, is used to analyze data from a biological assay. Inferences, depending only on the ranks of the observations, are made about the potency and about the validity of assumptions made in the analysis. Inferences are made in both Bayesian and sampling theory frameworks. An example of parallel line assay is given.
On the COLTON Model for Clinical Trials with Delayed Observations‐Dichotomous Responses
Authors: Langenberg P. , Srinivasan R. 
Published: May 2007

AbstractIn the COLTON model for clinical trials a choice is to be made between two medical treatments where there is a known patient horizon N. In an earlier paper we studied the COLTON model under the additional assumption that there is a time lag between the administration of the treatments and the availability of the responses where the responses are normally distributed. Here we extend the results of the earlier paper to the case where responses are dichotomous. The relative performance of two simple procedures for dealing with the patients who arrive during the waiting period between the end of the administration of treatment in the trial phase and observation of the final trial response is discussed within a BAYESIAN framework.
Estimation of the P(CS) with a Computer Program
Authors: Dudewicz Edward J. 
Published: May 2007

AbstractIn the area of ranking and selection, recent papers have presented procedures which attempt to allow experimenters to take at least partial advantage of more‐favorable configurations of the population parameters (compared to the least‐favorable configuration). The current paper presents a computer program which allows experimenters to dispense with all of inequalities, an indifference‐zone, and known equal variabilities in their assessment of the probability of correct selection. It has additional uses in implementation of recently‐proposed sequential adaptive selection procedures.
How Large is the Probability for the Estimate of a Variance Component to be Negative?
Authors: Verdooren L. R. 
Published: May 2007

AbstractFor a balanced one‐way classification, where the normally distributed observations obey a random modelyij=μ+bi+cijwith two variance components var (bi) = δand var (cij) = δ, the probability is given that the analysis of variance estimate of δwill be negative. This probability depends on δ/δand the degrees of freedom in the ANOVA table. Tables for this probability are given. If the normally distributed observations obey an intra‐class correlation model, the probability that the Mean Square between groups is smaller than the Mean Square within groups can also be evaluated from the given tables.
Rank Tests for correlated Random Variables
Authors: Brunner E. , Neumann N. 
Published: May 2007

AbstractIn this paper we consider the asymptotic distribution of linear rank‐statistics allowing certain dependencies between the random variables. General theorems will be given, from which the results contained in SEN(1967a, 1967b, 1968), MEHRA/SEN(1969) and PURI/SEN(1971) can be derived. Applying these theorems we can derive ranktests for the two‐sample problem for tied observations, for the two‐factor mixed model with random interaction and for a hierarchical design. The distribution of the proposed teststatistics for small sample sizes is considered by Monte‐Carlo studies.
Models for irreversible processes, based on cross‐sectional data
Authors: Bauer P. , Binder K. , Husinski I. , Kleinert W. , Künzel W. , Scheiber V. , Überhuber C. W. , Westphal G. , Wohlzogen F. X. 
Published: May 2007

AbstractThe analysis of the time dependent behavior of an irreversible all‐or‐none process on the basis of data from cross sectional surveys requires special methods. Assuming a pure death process three models of different degree of sophistication have been developed, mathematically analyzed and applied to one particular example: the caries attack on the permanent teeth of children.
A Class of Ratio Cum Product‐Type Estimator in Double Sampling
Authors: Sisodia B. V. S. , Dwivedi V. K. 
Published: May 2007

AbstractA class of ratio cum product‐type estimator is proposed in case of double sampling in the present paper. Its bias and variance to the first order of approximation are obtained. For an appropriate weight ‘a’ and a good range of α‐values, it is found that the proposed estimator is more efficient than the set of estimator viz., simple mean estimator, usual ratio and product estimators, SRIVASTAVA's estimator (1967), CHAKARBARTY's estimator and product‐type estimator, which are in fact the particular cases of it. The proposed estimator is as efficient as linear regression estimator in double sampling at optimum value of α.
Four Factor Balanced Optimal Designs of Resolution V in Terms of a Modified Trace Criterion
Authors: Nigam A. K. , Gupta V. K. , Bora A. C. 
Published: May 2007

AbstractBalanced optimal two level fractional factorial designs of resolution V have been reported in series of papers by SRIVASTAVA and CHOPRA (1971a, 1971b, 1974) and CHOPRA and SRIVASTAVA (1973a, 1973b). The optimality criterion considered by them is the trace optimality which implies minimisation of the average variance of the estimated effects which include the general mean μ, main effects, Ai, and first order interactions, Aij. In the present work some new optimal designs have been obtained on the basis of a modified criterion of trace optimality. The criterion requires minimisation of the average variance of each of the main effects, two factor interactions, etc. separately instead of minimising average variance of all the estimated effects.
Measuring Pairwise Agreement Among Many Observers. II. Some Improvements and Additions
Authors: Schouten H. J. A. 
Published: May 2007

AbstractWeighted kappa was defined as a measure of pairwise interobserver agreement for the case where the observers judging one subject are not necessarily the same as those judging another subject. In this paper improved formulas for the large sample variance of the weighted kappa statistic are derived, a new definition of interclass kappa coefficients is suggested, and the intraclass correlation coefficient is shown to be a special case of weighted kappa.
Minimum Norm Invariant Quadratic Estimation of a Covariance Matrix in Linear Model
Authors: Chaubey Yogendra P. 
Published: May 2007

AbstractA general linear model with a known covariance structure is considered. The method of Minimum Norm Quadratic estimation extending RAO'S (1972) argument is outlined. This method is illustrated for a particular model where it is noted that MINQE used for estimating intraclass correlation coefficient yields the maximum likelihood estimate.
Detection of Interactive Effects in Carcinogenesis
Authors: Hamilton M. A. 
Published: May 2007

AbstractThe multistage theory for cancer is used to derive models for independent effects and for interactive effects of two carcinogenic agents. The derivation assumes that a tumor is of single cell origin and that a normal cell is transformed to a cancer cell by undergoing a finite number of irreversible, heritable, mutation‐like transitions. The interactions enter the proposed models at the level of single cell transition rates rather than, as is conventional, at the level of animal response proportions. Suggestions are given for the design and analysis of fixed time, binary response, two factor, cancer bioassay experiments.
Equi‐replicated balanced block designs generated by a balanced matrix
Authors: Brzeskwiniewicz H. 
Published: May 2007

AbstractIn this paper it is shown that if N= \documentclass{article}\pagestyle{empty}\begin{document}$ \mathop \sum \limits_{i = 1}^{S_h} $\end{document} cihNih, where cih are some non‐negative integer numbers and Nih are such incidence matrices that Ah = \documentclass{article}\pagestyle{empty}\begin{document}$ \mathop \sum \limits_{i = 1}^{S_h} $\end{document} i Nih is a balanced matrix defined by SHAH (1959), for h = 1, 2,…, p, then a block design with an incidence matrix Ñ = [N, N,…,N] is an equi‐replicated balanced block design. Here the balance of a block design is defined in terms of the matrix M0 introduced by CALIŃSKI (1971).
Measurement of the Relation of Two Characteristics
Authors: Hellmich K. 
Published: May 2007

AbstractThe four‐field table measure K (appearing as K1, K2), which is only a coefficient‐measure, can, by means of a useful transformation, be transformed into a real measure k by means of a graduated scale. The measure k can be compared with other k‐values and, futhermore, reveals directly, by how many per cent the one characteristic can be looked upon as being determined by the other characteristic of the two characteristics under review.
Fluctuations in the Size of Isolated Single‐Species Populations and Natural Selection
Authors: Frisman E. Ya. , Shapiro A. P. 
Published: May 2007

AbstractThis paper discusses the basic types of dynamical behavior of populations obtained in discrete models, such as monotonous dynamics, stable limited cycles, and chaotic variations. All these modes are shown to have possibly arisen in the evolution of limited populations under the effect of density‐independent selection. This effect together with that of density‐dependent non‐selective factors has been termed F‐selection, which is characterized by independence of relative fitnesses from population density, whereas populations may be ecologically limited; in other words, absolute fitnesses prove to be a function of population size. The characteristic of F‐selection is to be not sensitive to changes in population size but to lead to fluctuations, that create conditions for achieving density‐dependent selection.
Lecture‐free biochemistry
Authors: Minderhout Vicky , Loertscher Jennifer 
Published: May 2007

AbstractBiochemistry courses at Seattle University have been taught exclusively using process oriented guided inquiry learning (POGIL) without any traditional lecture component since 1997. In these courses, students participate in a structured learning environment, which includes a preparatory assignment, an in‐class activity, and a follow‐up skill exercise. Instructor‐designed learning activities provide the content of the course while the cooperative learning structure provides the content‐free procedures that promote development of critical process skills needed for learning. This format enables students to initially explore a topic independently, work together in groups to construct and refine knowledge, and eventually develop deep understanding of the essential concepts. These stages of exploration and concept development form the foundation for application to high level biochemical problems. At the end of this course, most students report feeling confident in their knowledge of biochemistry and report substantial gains in independence, critical thinking, and respect for others.
A case‐based approach increases student learning outcomes and comprehension of cellular respiration concepts
Authors: Rybarczyk Brian J. , Baines Antonio T. , McVey Mitch , Thompson Joseph T. , Wilkins Heather 
Published: May 2007

AbstractThis study investigated student learning outcomes using a case‐based approach focused on cellular respiration. Students who used the case study, relative to students who did not use the case study, exhibited a significantly greater learning gain, and demonstrated use of higher‐order thinking skills. Preliminary data indicate that after engaging with the case study, students were more likely to answer a question addressing misconceptions about cellular respiration correctly when compared with students who did not use the case study. More rigorous testing is needed to fully elucidate whether case‐based learning can effectively clarify student misconceptions related to biological processes.
The eyes have it
Authors: White Harold B. 
Published: May 2007

AbstractMolecular evolution provides an interesting context in which to use problem‐based learning because it integrates a variety of topics in biology, biochemistry, and molecular biology. This three‐stage problem for advanced students deals with the structure, multiple functions, and properties of lactate dehydrogenase isozymes, and the related evolutionary trade offs of gene sharing versus gene duplication among their corresponding genes. It has directive elements that require students to find and read classic articles, review thermodynamic principles, and apply their understanding to a mythical world wherein dinosaurs continued to evolve. The science fiction writing assignment that brings closure to the problem transformed the problem with respect to student interest and engagement.
Using restriction mapping to teach basic skills in the molecular biology lab
Authors: Walsh Lauren , Shaker Elizabeth , De Stasio Elizabeth A. 
Published: May 2007

AbstractDigestion of DNA with restriction enzymes, calculation of volumes and concentrations of reagents for reactions, and the separation of DNA fragments by agarose gel electrophoresis are common molecular biology techniques that are best taught through repetition. The following open‐ended, investigative laboratory exercise in plasmid restriction mapping allows students to gain technical expertise while simultaneously exploring the utility of gel electrophoresis and restriction mapping. Because of its interpretive nature, this project also provides data suitable for a written report, and can thus be used to reinforce lessons on figure presentation and science writing skills.