bluuebunny/crossref_metadata_2025 huggingface dataset:
Maximum Likelihood Estimation of Exponential Polynomial Rate for Poisson Data
Authors: Mathers C. D.
Published: May 2007

The heterogeneous Poisson process with discretized exponential quadratic rate function is considered. Maximum likelihood estimates of the parameters of the rate function are derived for the case when the data consists of numbers of occurrences in consecutive equal time periods. A likelihood ratio test of the null hypothesis of exponential quadratic rate is presented. Its power against exponential linear rate functions is estimated using Monte Carlo simulation. The maximum likelihood method is compared with a log‐linear least squares techniques. An application of the technique to the analysis of mortality rates due to congenital malformations is presented.
Improved Generalized Ratio‐Cum‐Product Estimation
Authors: Singh R. Karan , Singh Gurdeep
Published: May 2007

In this paper, a generalized ratio‐cum‐product estimator for estimating the ratio (product) of two population means using auxiliary information on two other variables is given of which the estimators by SINGH (1969) and SHAH and SHAH (1978) are particular cases. The estimator is regeneralized when the covariance between two auxiliary variables is known.
Some Theoretical Aspects of Analysis in Half Diallel
Authors: Singh M. , Singh R. K.
Published: May 2007

The analysis of F1 and F2 half diallel has been discussed as compared to full diallel without reciprocal effects given by MATHER and JINKS (1971). In practice, mostly the half diallel (one‐way) crosses are prepared and erroreously analysed using the least square estimates of full diallel without reciprocal effects. The H1 and H2, however, appeared to be over estimated when full diallel without reciprocal effects estimates were used in place of those of half diallel. Least square estimates were also obtained assuming heterogeneity of error components between parents and F1/F2 families.
A Note on Life Table Construction
Authors: Nair N. Unnikrishnan
Published: May 2007

In this article a modification to the CHIANG'S method of construction of the current life table is presented by using a new set of estimates of nax, derived under certain simplified assumptions.
Statistical Significance of Mutation Frequencies, and the Power of Statistical Testing, Using the Poisson Distribution
Authors: Zar Jerrold H.
Published: May 2007

The Poisson distribution may be employed to test whether mutation frequencies differ from control frequencies. This paper describes how this testing procedure may be used for either one‐tailed or two‐tailed hypotheses. It is also shown how the power of the statistical test can be calculated, the power being the probability of correctly concluding the null hypothesis to be false.
Two New Discrete Distributions
Authors: Gupta Devendra
Published: May 2007

CONSUL and JAIN (1973a) introduced a generalized Poisson distribution, which has applications in reliability theory and many biometric studies, and described some of its properties. Here we obtain two new distributions treating two of the parameters of the above distribution as random variables having gamma and absolute value distributions. One of the new distributions is related to the negative binomial distribution. Their moments also have been obtained.
Admissible Regions in a Simplex of Identity Coefficients
Authors: Karigl G.
Published: May 2007

Genealogical relationships between any number of individuals are characterized, from the genetic point of view, by the probabilitiea of ell poeeible gene identity states occuning at an autosomel locus. However, only a eubepece of the apace of all probabilities ie in fact accemible to any relationehip. Badon a theorem of THOMPSON (1076). a characterization of the admissible region in the simplex of all condeneed identity coefficients of two non‐inbred individuals is presented. Further s similar result in the caae of detailed coefficients is given.
Competing Risk Analysis for Life Table Data with known Observation Times
Authors: Yeh C. , Le C. , McHugh R.
Published: May 2007

Several models have been proposed for the analysis of cohort mortality in the presence of competing risks (a recent account is given by ELANDT‐ JOHNSON and JOHNSON, 1980, Chapter 12).

This paper describes a maximum likelihood approach to the analysis of followup data in life table format for the case of two competing risks—a specific cause and its competing complement. The model developed uses a robust survivorship assumption — the piecewise exponential — and takes into account information on time to death and time to withdrawal.
Examples of non‐trivial efficiency‐balanced designs withb=v+1
Authors: Kageyama Sanpei
Published: May 2007

This note provides examples of binary efficiency‐balanced block designs withb=v+1, having no complete blocks, which are unequal‐replicated and unequal‐blocksized from a biometrical and agricultural standpoint.
Un Point de Depart pour les Methodes Iteratives de Regression. Application a la Regression Lineaire Robuste
Authors: Dolla A. , de Beauville J. P. Asselin
Published: May 2007

The importance of the starting point for iterative robust regression is well known since the ordinary least square solution often used doesn't always give good results.

We suggest a new method called “regression by the sectors” (RPS) as a starting point to an iterative windsorisation of the original data (ITER).

We used artificial samples to compare RPS and other quick techniques of fit: regression by median, Hinich‐Talwar's method, L1 norm minimization. Besides RPS‐ITER algorithm is tested (examples and simulations) in relation to algorithms using different starting points associated to ITER.

The results show the superiority of RPS‐ITER.
Estimation of Parameters in Binomial Crossover Designs
Authors: Le C. T. , Gomez‐Marin O.
Published: May 2007

Maximum Likelihood Estimation of order and treatment effects are derived for Binomial Crossover Designs. All estimators and estimated covariance and variances have closed forms and can be easily evaluated. These results are useful for use in multi‐center clinical trials.
Comparison of Populations Based on Attribute Data, when Covariance Matrices are Unequal
Authors: Misra R. K.
Published: May 2007

Mahalanobis—like distance indices B2 and G2 of BALAKRISHNAN and SANGHVI (1968) are employed to compare multinomial populations of proportions in human data. Recently, BOWERING and MISRA (1982) employed these methods, with modifications, in a different field viz. to compare fish stocks, based on meristic characters. The method of BALAKRISHNAN and SANGHVI (1968), however, assumes equality of covariance matrices, which is doubtful with multinomial populations of proportions. In this paper a statistical method for comparing such populations (where covariance matrices are not equal) is presented. Also, a feature of the G2 method of BALAKRISHNAN and SANGHVI (1968) is discussed, which makes its statistical status a little more clear.
Übér die Anwendung verschiedener Diskriminationsverfahren
Authors: Eichhorn Chr.
Published: May 2007

Applications of methods of discriminant analysis are considered for normal distributions with common or differing variances and for distributions of unknown type, and an example is given. Results are discussed with respect to available programs, and the different methods of discriminant analysis are compared.
Randomness and Order in a Forest with Trees in Rows‐a Case Study
Authors: Stoyan D. , Ohser J.
Published: May 2007

The correlations between intertree distances and stem volumina of trees in an artificial pine wood with trees in rows are studied. Several stochastic models are suggested, and methods of the theory of random measures are used. A method for estimating the produce of woods of the type considered is suggested.
Erweiterung des Mantel‐Haenszel‐Tests auf K(>2) Gruppen
Authors: Zimmermann H.
Published: May 2007

The Mantel‐Haenszel‐Test, which is widely used as the so called logrank‐test for survival data, was developed for two groups with ordinally scaled data. It is shown that it can be applied to more than two groups, and that the test statistic is easily derived from the F‐statistics of standard oneway analysis of variance procedures.
A Truncated Proportional Hazards Test
Authors: Lachenbruch P. A. , Seibert S. , Amini S.
Published: May 2007

We present two truncated proportional hazards tests. The first, which is applicable to those cases in which the time of action of an agent or treatment is known, was studied in two forms: One uses expected Fisher information and the other observed Fisher information. In this case the expected information statistic, C1(a0), had properties superior to the observed information statistic and is recommended. The use of the X2 distribution with one degree of freedom for percentiles appears to be satisfactory. When the time of action is unknown, a statistic based on the maximum of the C1(a) statistics is used. A simulation study gives empirical percentiles for the Max C1(a) statistic which agree with those given in a study by Muenz, Green and Byar (1977).
Merging Spline Approximations with Analysis of Nonlinear Regression Models
Authors: Onukogu Ike B.
Published: May 2007

The paper outlines a method of analysis of intricically non‐linear regression functions. The nonlinear model is first approximated by a cubic spline function. Thereafter, the standard methods of analysis in linear models are applied to obtain estimates and test statistics.
Gaußsche Markovketten zweiter Ordnung
Authors: Berg L.
Published: May 2007

We find the general form of the proper Gaussian Markov chains of second order and give an example for them. Comparing with the Gaussian Markov processes they can be used as an improved growth model.
A generalized Friedman test for data defined by intervals
Authors: Schemper M.
Published: May 2007

If observations are restricted in such a way that only intervals covering the true but hidden values are known—situations found in clinical studies or analyzing laboratory data‐standard nonpara‐metric procedures fail. The present paper suggests the use of generalized Friedman tests, if the sample consists of nk observations, with one observation from each of k treatments in each of in blocks. Furthermore the proposed test enables Friedman‐type analyses of censored data. An example is given and a computer program facilitating the use of the test is introduced.
Multiple Comparisons of Polynomial Distributions
Authors: Royen Th.
Published: May 2007

Asymptotically correct 90 and 95 percentage points are given for multiple comparisons with control and for all pair comparisons of several independent samples of equal size from polynomial distributions. Test statistics are the maxima of the X2‐statistics for single comparisons. For only two categories the asymptotic distributions of these test statistics result from DUNNETT'S many‐one tests and TUKEY'S range test (cf. MILLER, 1981).

The percentage points for comparisons with control are computed from the limit distribution of the test statistic under the overall hypothesis H0. To some extent the applicability of these bounds is investigated by simulation. The bounds can also be used to improve Holm's sequentially rejective Bonferroni test procedure (cf. HOLM, 1979).

The percentage points for all pair comparisons are obtained by large simulations. Especially for 3×3‐tables the limit distribution of the test statistic under H0 is derived also for samples of unequal size. Also these bounds can improve the corresponding Bonferroni‐Holm procedure.

Finally from SKIDÁK's probability inequality for normal random vectors (cf. SKIDÁK, 1967) a similar inequality is derived for dependent X2‐variables applicable to simultaneous X2‐tests.
On Combination of Ratio and PPS Estimators
Authors: Pandey S. K. , Singh R. Karan
Published: May 2007

AGARWAL and KUMAR (1980) proposed an estimator, combining ratio and pps estimators of population mean and proved that the proposed estimator would always be better (in minimum mean square error sense) than the pps estimator or the ratio estimator under pps sampling scheme for optimum value of constant k (parameter). The optimum value of k is rarely known in practice, hence the alternative is to replace k from the sample‐values. In this paper, an estimator depending on estimated optimum value of k based on sample‐values, under pps sampling scheme is proposed and studied.
Tables and Applications of the Bonferroni t‐Statistics: A Revision of Dunn's Simultaneous t‐Tests
Authors: Gottlieb R. , Lienert G. A. , Ludwig O. , Rockenfeller K.
Published: May 2007

Tables for Bonferroni‐adjusted significance levels of Student's t are provided for r = 3(1)30(5)50 etc. and alphas of 0.05, 0.01 and 0.001. The tables are suggested for various applications, for example in replacing analysis of variance of k samples by r simultaneous t tests. Use of the tables is shown by numerical examples.

The adjustment of alpha for improving the efficiency of testing is made by WILKINSON for orthogonal comparisons and by HOLM for nonorthogonal comparisons.
The Matched Pairs Problem with Exponential Variates
Authors: Lachenbruch P. A. , Woolson R. F.
Published: May 2007

Two classes of tests for the hypothesis of bivariate symmetry are studied. For paired exponential survival times (t1j, t2j), the classes of tests are those based on t1j‐t2j and those based on log t1j–log t2j. For each class the sign, signed ranks, t and likelihood ratio tests are compared via Pitman's criterion of asymptotic relative efficiency (ARE). For tests based on t1j — t2j, it is found that: (1) the efficacy of the paired t depends on the coefficient of variation (CV) of the pair means, (2) the signed rank test has the same ARE to the sign test as for the usual location problem.

For tests based on log t1j — log t2j, the ARE comparisons reduce to the well‐known results for the one‐sample location problem for samples from a logistic density. Hence, the signed rank test is asymptotically efficient. Furthermore, analyses based on log t1j — log t2j are not complicated by the underlying pairing mechanism.
On Population and Sample Measures for the Simple and Multiple Linear Relation
Authors: Goria M. N.
Published: May 2007

Here population measures and their sample analogue for the linear relation between two or more variables are proposed. Two approximations for the measure in the general case are derived and these are then compared with the exact measure in a special case.
Tests of Hypotheses for the General Gauss‐Markov Model
Authors: Oktaba W.
Published: May 2007

Some theorems connected with testing the linear hypotheses in the case of the fixed general Gauss‐Markov model are given. The assumptions are as follows. Let y = Xβ + e be a fixed model where residuals ea, …, en being coordinates of the random column vector e are normally distributed with means zero and a known covariance matrix α2V non‐singular or singular and an unknown scalar parameter α2. Suppose that the known matrix X is n × p with rank r(X) = r⩽pn, where pis a number of coordinates of the unknown parameter vector β. The expected value of the random vector y with n coordinates constitutes the vector α(y) = Xβ. The formulas of the test functions (cf. theorems 2.1, 2.2, 2.3) contain c‐inverse matrices T− (defined by the condition TT−T = T), and some others when T = V + XBX′ and B = B′ is any symmetric matrix such that (cf. RAO (1971), OKTABA (1982)) r (V:X) = r (V + XBX′); (V:X) denotes matrix with two submatrices V and X.

Mutual orthogonal conditions for a set of estimable parametric functions are introduced and used in the decomposition of the sum of squares for the linear hypothesis into orthogonal sums of squares each on one degree of freedom. Each of these hypotheses can be verified by the random variable F as in the analysis of variance. Some applications (cf. sections 4.1 and 4.2) of three theorems are given. Calculations without an electronic computer are rather tedious.
A Note on the Estimation of Coverage Errors in Demographic Data
Authors: Nour El‐Sayed
Published: May 2007

A simple formula for the lower bound of coverage errors in demographic data is obtained. The formula is derived under general assumptions, the validity of which is discussed. Three numerical examples are given.
Application of Statistical Classification Technique to the Forecasting of Outcomes of Diseases
Authors: Khakhubia Ts. G. , Gvantseladze L. G. , Felker V. M.
Published: May 2007

A probabilistic statistical model based on statistical classification is proposed for disease outcome forecasting. In particular, cardiac infarction outcome is forecasted and a table of the forecasting results is given. A conclusion of theoretical character is made about the preferable use of a non‐uniform band width in the construction of a general histogram for unknown distribution density estimation.
Estimation of Relative Risk Under Variable Multiple Matching
Authors: Ejigou A.
Published: May 2007

When disease incidence is low, the odds ratio, which closely approximates relative risk, is estimated optimally in a closed form using a variable matching ratio in a retrospective design. The model also enables one to assess the homogeneity of the odds ratio from the same one matched sample. Analogous procedures are shown to hold for the prospective design.
Some Bounds on Parameters of Efficiency‐Balanced Block Designs
Authors: Ceranka B. , Kozlowska M.
Published: May 2007

Bounds on the eigenvalue of theC‐matrix with respect toRand the number of blocks for efficiency‐balanced block designs are given.

AMS 1970 Subject Classification: 62K10
Designing the Sample Size for Non‐parametric, Multivariate Tolerance Regions
Authors: Ackerwn H. , Abt K.
Published: May 2007

In supplementation of the work by ABT (1977, 1982) and ACKERMANN (1980, 1983) extensive ta.bles and approximite formulae are provided for the determination of the sample size for constructing “inner” and “outer” limits of non‐parametric multivariate tolerance regions.
Variants of the Varimax Rotation Method
Authors: Frankel E.
Published: May 2007

In the present paper we present an example proving that the Varimax rotation method commonly used in factor analysis (see H. F. KAISER, 1958) need not give a unique solution. We also show that changing the original algorithm more than one local maximum of the criterion “V” can be achieved. Hence the loadings of factors and practical interpretations of solutions are affected in this way.
Jeffreys' Likelihood Ratio for the 2×2‐Table — A Monte Carlo Study —
Authors: Böhning D. , Rolling H. , Kaufhold G.
Published: May 2007

Jeffreys' approach for analyzing a 2×2‐table is discussed via a Monte Carlo study. The main findings are reported.
Unconditional Tests of Hypotheses Concerning Relative Risk
Authors: Bennett B. M.
Published: May 2007

The problem of estimation of, and statistical tests for, the relative risk (=α) from samples in which there is matching on covariates have been discussed by various authors (Cox, 1970; MANTEL and HAENSZEL, 1959) using the approach of conditional variates. This paper discusses log LR (likelihood ratio) tests of hypotheses concerning α, as based on one or more sets of matched samples. ApproximateX2tests are also developed for the hypotheses concerning α. An example is presented which illustrates the proposed tests of significance (Table 1).
The Structure of Ellipsoidal Distributions I. Canonical Analysis
Authors: Jensen D. R.
Published: May 2007

This study is concerned with the structure of variables having ellipsoidal distributions. In Part I it is shown that many normal‐theory results in canonical analysis are exact for all ellipsoidal distributions under a specified model for sampling. In Part II similar conclusions are drawn regarding the use of principal components. These findings suggest using normal‐theory procedures in canonical and principal components analyses as approximate large‐sample procedures for distributions attracted to ellipsoidal stable laws.
The Negative Binomial Distribution of Orderkand Some of Its Properties
Authors: Philippou A. N.
Published: May 2007

The negative binomial distribution of orderkis introduced and briefly studied. First it is shown that it is a proper probability distribution. Then its probability generating function, mean and variance are derived. Finally it is shown that the number of trials until therthkth consecutive success (r≧ 1,k≧ 1) in independent trials with constant success probabilityp(0 <p< 1) is distributed as negative binomial distribution of orderk.The present paper generalizes results of SHANE (1973), PHILIPPOU and MUWAFI (1982), and PHILIPPOU, GEORGHIOU and PHILIPPOU (1982).
Characterizations of Continuous Binomial and Negative Binomial Mixtures
Authors: Papageorgiou H.
Published: May 2007

Characterizations are given for binomial (n, ϑ) and negative binomial (k, ϑ) mixtures in terms of the regression function of the mixing random variableYon the mixture variableX.In both casesYis the parameter ϑ and the mixing distribution is a continuous distribution on (0, 1) and on (0, ∞) respectively. Biological applications are indicated.
Linear Regression Model with Random Coefficients
Authors: Raja J. Sundara
Published: May 2007

Estimation of linear regression with random coefficients is studied in this work. Non‐negative estimates of variances are proposed. The result is a modification of works of SRIVASTAVA et al. (1981).
Estimates of a Treatment Effect Based on Censored Data Rank Tests
Authors: Rosenkranz G.
Published: May 2007

Linear rank test statistics are applied to the problem of estimating a treatment effect if two sets of censored failure time data are compared and the distributions of the log‐failure times of the two samples are assumed to differ only in location. Rank tests for this accelerated failure time model are reviewed and Hodges‐Lehmann type estimates for the shift parameter are proposed. Properties of these estimates are investigated, computational aspects are discussed and an example is presented.
Randomization Modelling of the Crossover Experiment for Clinical Trials
Authors: Gomez‐Marin O. , McHugh R. B.
Published: May 2007

The two‐period cross‐over experiment for clinical trials has been examined by several writers following a Gaussian linear model approach. Some authors have expressed interest in the “derivation of the finite permutation model” and have pointed out that the randomization approach to modeling the two‐period cross‐over design “would highlight the importance of randomizing the subjects to the two groups as a basis for inference”. However, in the literature, there is no development of the randomization approach to this important design.

In this paper, after a statement of the experimental design and formulation of the observation random variables of the finite population, two additive randomization models—one with residual effects, the other without—which are the analogues of Grizzle's Gaussian models, are derived. Statistical inference is developed for these randomization models and the results are compared with those of the corresponding Gaussian models. Also, exact inference based upon Fischer's approach is presented.
On the Estimation of the Population Mean with Known Coefficient of Variation
Authors: Upadhyaya L. N. , Singh H. P.
Published: May 2007

For the estimation of population mean a class of estimators has been proposed when the coefficient of variation is known and its efficiency is compared with the usual unbiased estimator and the estimators suggested by various researchers. The properties of the proposed class of estimators have been also discussed in the case of normal population.
A Lagrangian Gamma Distribution of the Second Kind
Authors: Rao B. Raja , Janardan K. G. , Schaeffer D. J.
Published: May 2007

The distribution of the time T for the occurrence of the rth event is derived in a linear function Poisson process, which belongs to a recently introduced family of distributions (JANARDAN and RAO, 1981), called Lagrangian distributions of the second kind (LD2). In analogy with the ordinary Poisson process, the distribution of the random variable T has been termed the Lagrangian Gamma distribution of the second kind (LG2); several of its properties and special cases are studied. The frequency function is graphed for some parameter values.
A Comparison of Tests for Marginal Homogeneity in Square Contingency Tables
Authors: Krauth J.
Published: May 2007

Several asymptotic tests were proposed for testing the null hypothesis of marginal homogeneity in square contingency tables withrcategories. A simulation study was performed for comparing the power of four finite conservative conditional test procedures and of two asymptotic tests for twelve different contingency schemes for small sample sizes. While an asymptotic test proposed by STUART(1955) showed a rather satisfactory behaviour for moderate sample sizes, an asymptotic test proposed by BHAPKAR(1966) was quite anticonservative. With no a priori information the performance of (r‐ 1) simultaneous conditional binomial tests with a Bonferroni adjustment proved to be a quite efficient procedure. With assumptions about where to expect the deviations from the null hypothesis, other procedures favouring the larger or smaller conditional sample sizes, respectively, can have a great efficiency. The procedures are illustrated by means of a numerical example from clinical psychology.
Interactions in Contingency Table Analysis
Authors: Töwe J. , Bock J. , Kundt G.
Published: May 2007

Proceeding from Lancaster's definition of interactions between random variables, the authors set up a model for contingency tables of any dimension. Three‐dimensional contingency tables are used as an example to discuss first and second order interaction effects, and the conventional independence are expressed by hypotheses concerning interaction effects. The opinions of other authors regarding second order interaction effects are discussed.
A Note on Resolvable Incomplete‐Block Designs
Authors: Patterson H. D. , Williams E. R. , Paterson L.
Published: May 2007

KHARE and FEDERER (1981) have proposed a method for constructing resolvable incomplete‐block designs with, they claim, higher efficiencies than those of the α‐designs described by PATTERSON and WILLIAMS (1976a). This claim is shown here to be unfounded. The best α‐designs have higher efficiencies than the Khare and Federer designs, and can be constructed straightforwardly using the concise table of generating arrays in PATTERSON, WILLIAMS and HUNTER (1978).
Estimation of Fixed and Random Effects in the Functional Nonlinear Errors‐in‐Variable Model
Authors: Johnson P. M. , Milliken G. A.
Published: May 2007

Consider an experiment where a nonlinear continuous functional relationship exists betweenyandX.Assume that this relationship has been measured atnreplicated points ofXfrom each ofttreatments or populations. Assume further that theXare fixed unknown vectors and that the location parametervis either a fixed unknown vector or a vector of random variables. In the first case various linear hypotheses are to be tested aboutv, such as tests for main effects and interaction; in the second case, the mean and variance of the random variablevare to be estimated. A two‐step procedure based on asymptotic theory is presented to test hypotheses or develop estimates for the fixed effects or random effects functional errors‐in‐variable model. An example of a one‐way random effects model is given.
A Note on Successive Sampling Over Two Occasions
Authors: Sisodia B. V. S.
Published: May 2007

In this note, an attempt has been made to study the effect on MVLUE of a population mean on the second occasion in successive sampling when sample values of correlation and regression coefficients are used in it. It was found that increase in the MSE of derived biased estimator is of the orderq2ρ2which may be negligible till the proportion of unmatched units (q) and correlation coefficient (ρ) are quite small.
On the Estimation of Population Mean in Stratified Sampling
Authors: Kaur Parvinder
Published: May 2007

When stratified random sampling is used for the estimation of population mean, use of ‘Combined ratio estimator’ is well known. Some improved estimators for population mean are proposed which are better than ‘Combined ratio estimator’ and some other well known existing ones, from the point of view of bias and mean square error. An empirical illustration is given.
An Efficient Regression Type Estimator in Survey Sampling
Authors: Kaur Parvinder
Published: May 2007

For the estimation of population mean in simple random sampling, an efficient regression‐type estimator is proposed which is more efficient than the conventional regression estimator and hence than mean per unit estimator, ratio and product estimators and many other estimators proposed by various authors. Some numerical examples are included for illustration.
Horvitz‐Thompson Strategies versus Rao, Hartley and Cochran's Strategy
Authors: Gabler S.
Published: May 2007

The Rao, Hartley and Cochran strategy cannot be improved by a Horvitz‐Thompson strategy with an inclusion probability proportional to sizes sampling scheme. This is a striking contradiction to the paper of AGARWALand KUMAR(1982).
Robustness of Sequential Tests for Means
Authors: Rasch D.
Published: May 2007

Three sequential tests of the null hypothesis, μ = μ0, versus an alternative of the form (μ − μ0)2= =σ2d2 are compared for different forms of violation of the underlying normal assumption. 10000 samples were simulated for d=0.6; 1.0 and 1.6 (σ2 = 1), four (α, β)‐combinations and seven alternative distributions. The results show that for small d‐values one test is robust for α and another for β. For large d all tests can be used.
The Problem of Nucleolar Number in Cell Nuclei and in Sections of Cell Nuclei
Authors: Voss K. , Roth K.
Published: May 2007

In this paper the mean number N of nucleoli of cell nuclei and the relative frequency PN of cell nuclei with N nucleoli are investigated. To solve the first problem, the stereological model of convex shaped nuclei and nucleoli and the assumption of randomly‐isotropically distributed objects in space are used. The model is developed for non‐vanishing thickness T of tissue sections. The relationship between the unknown number N of nucleoli in cell nuclei and the mean number n of nucleoli in nuclear sections determined by counting is N = n (D+T)/(d + T). Here D and d are the mean values of caliper diameter for nuclei and for nucleoli, resp. The second problem is illustrated by means of some biomedical examples: The relative frequency PN of cell nuclei with N nucleoli can be approximated by a generalized Poisson distribution in all investigated cases. Therefore the mean nucleolar number N is the essential parameter to describe the frequencies of cell nuclei with different numbers of nucleoli.
The Power Function of the Test for ‘No Three Factor Interaction’ in 2×2×2 Contingency Tables
Authors: Haber M.
Published: May 2007

Three approximations to the power function of the chi‐square test for the hypotheses of ‘no three factor interaction’ in a 2 × 2 × 2 contingency table are introduced and compared. The first method is based on the sampling distribution of the logarithm of the odds ratio, the second‐on the non‐central X2 distribution and the third—on the conditional distribution of a cell entry. The last method is found to provide the closest approximation under various alternative hypotheses and sample sizes.
On Two Auxiliary Variates in Ratio Method of Estimation
Authors: Agarwal S. K. , Kumar Pranesh
Published: May 2007

A ratio type estimator using two auxiliary variates is suggested which is found to be more practicable than that of AGARWAL'S (1980) estimator.
Canonical Correlation as a Discriminant Tool in a Periodontal Problem
Authors: Lindsey H. , Webster J. T. , Halpern S.
Published: May 2007

This paper illustrates two advantages of using canonical correlation as a tool in the discriminant problem, with more than two populations, rather than the more familiar Anderson discriminant function. These advantages are: i) simultaneous test of significance as to whether the means of the populations differ and ii) given that the means differ, a graphic tool to illustrate the nature of the difference between the populations. If there are natural groupings of the populations, an analytic technique is also available to augment i). This latter property is also demonstrated in the accompanying application.
Development and validation of bioanalytical methods for imidafenacin (KRP‐197/ONO‐8025) and its metabolites in human urine by using liquid chromatography‐tandem mass spectrometry
Authors: Masuda Yuichi , Kanayama Norihiro , Manita Shigeru , Ohmori Satoshi , Ooie Tsuyoshi
Published: May 2007

New bioanalytical methods have been developed for the determination of imidafenacin (KRP‐197/ONO‐8025, IM), a novel antimuscarinic drug developed for the treatment of overactive bladder, and its metabolites, M‐2, M‐3, M‐4, M‐6 and M‐8 (method 1), M‐5 and M‐9 (method 2) in human urine by using liquid chromatography–tandem mass spectrometry. In each method, the urine sample was extracted by solid‐phase extraction, separated on a semi‐micro high‐performance liquid chromatography column using gradient elution and detected by tandem mass spectrometer with an atmospheric pressure chemical ionization or ionspray interface. Extraction recoveries of IM and metabolites were 81.4% or more. Calibration curves had good linearity in the concentration ranges 0.2–50 ng/mL for IM, M‐2, M‐3, M‐4, M‐6 and M‐8 (method 1) and 1–250 ng/mL for M‐5 and M‐9 (method 2), respectively. The accuracy and precision in the intra‐day and inter‐day reproducibility tests were within ±17.0 and 16.1% at the lowest concentrations, and within ±12.8 and 11.1% at higher concentrations, respectively. Using these analytical methods, excretion profiles of IM and its metabolites in human urine were successfully determined after oral administration of IM at the therapeutic dosage of 0.1 mg. Copyright © 2007 John Wiley & Sons, Ltd.
Convenient and rapid determination of cimetidine in human plasma using perchloric acid‐mediated plasma protein precipitation and high‐performance liquid chromatography
Authors: Jantratid Ekarat , Prakongpan Sompol , Foley Joe P. , Dressman Jennifer B.
Published: May 2007

This study demonstrates the analysis of cimetidine in human plasma with HPLC using a simplified sample preparation by protein precipitation with perchloric acid. Plasma cimetidine concentration was determined by plotting peak height ratio of cimetidine to ranitidine (internal standard, IS) against cimetidine concentrations in plasma. The cimetidine and ranitidine peaks were completely separated and no interference from plasma was observed. The lower limit of quantification (LLOQ) of the method was established at 0.1 µg/mL with a precision of 4.3% and a relative error of 1.9%. The average analytical recovery was >90% over the range of cimetidine concentrations (0.1–15.0 µg/mL). The linearity of calibration curve was excellent (r2 > 0.999). The within‐ and between‐day precision and accuracy, expressed as the coefficients of variation and relative error, were found to be less than 5%. Compared with previously reported methods, the analytical technique for cimetidine determination in human plasma presented here demonstrates comparable accuracy and precision, an acceptable analysis time, shorter and simpler sample preparation, and a reduced need for complicated equipment. The method presented here is simple and rapid, and the precision and sensitivity are appropriate for the determination of cimetidine in plasma in pharmacokinetic studies. Copyright © 2007 John Wiley & Sons, Ltd.
Sensitive determination of MDMA and its metabolite MDA in rat blood and brain microdialysates by HPLC with fluorescence detection
Authors: Tomita Mamoru , Nakashima Mihoko N. , Wada Mitsuhiro , Nakashima Kenichiro
Published: May 2007

Simultaneous determination of 3,4‐methylenedioxymethamphetamine (MDMA) and 3,4‐methylenedioxyamphetamine (MDA) in rat blood and brain microdialysates by high‐performance liquid chromatography with fluorescence detection (HPLC‐FL) was developed. Microdialysates were directly subjected to derivatization with 4‐(4,5‐diphenyl‐1H‐imidazol‐2‐yl)benzoyl chloride (DIB‐Cl). The DIB‐derivatives of MDMA, MDA and the internal standard, 1‐methyl‐3‐phenylpropylamine (MPPA), were isocratically separated on an ODS column using a mixture of 50 mm phosphate buffer (pH 7.0)–acetonitrile–methanol–2‐propanol (50:45:5:2, v/v/v/v %) as an eluent at a flow rate of 1.5 mL/min. The calibration curves of MDA and MDMA spiked to blood and brain microdialysates were linear over the ranges 2.5–500 and 5.0–1000 ng/mL, respectively. The detection limits of MDA and MDMA were 1.2 and 4.2 for blood and 1.3 and 4.8 ng/mL for brain, respectively. Additionally, the intra‐ and the inter‐assay precisions were lower than 5.6% for the blood and brain microdialysates (n = 4). The proposed method was successfully applied for the monitoring of MDMA and its metabolite MDA in rat blood and brain microdialysates, and the pharmacokinetic parameters of MDMA and MDA in the microdialysates after administration of MDMA (5 mg/kg, i.p.) with or without caffeine (20 mg/kg, i.p.) were evaluated. Copyright © 2007 John Wiley & Sons, Ltd.
Molecularly imprinted solid‐phase extraction combined with molecularly imprinted polymer‐sensor: a diagnostic tool applicable to creatine deficiency syndrome
Authors: Sharma Piyush Sindhu , Lakshmi Dhana , Prasad Bhim Bali
Published: May 2007

Primary creatine deficiency syndromes (CDS) are a new group of disorders caused by guanidinoacetate methyltransferase (GAMT) deficiency, which affects endogenous creatine biosynthesis with depletion of body creatine. A deficiency in creatine can be corrected by treatment with oral creatine supplementation and this necessitates a simple and sensitive screening method for early detection of creatine in dilute physiologic fluids. In this work an artificial receptor, molecularly imprinted polymer (MIP), for creatine was used both as a material for solid‐phase extraction (SPE) and as a sensing element in a voltammetric sensor. Using the combination of molecularly imprinted solid‐phase extraction (MISPE) with a complementary MIP sensor, the minimum detectable amount was found to be 0.0015 ng mL−1 (RSD = 1.3%, S/N = 3). The MISPE‐MIP sensor combination provided up to 60‐fold preconcentration, which was more than sufficient for achieving the required quantification limit 50 ng mL−1 (or 0.0025 ng mL−1 after 2 × 104‐fold dilution) for creatine in human blood serum. Copyright © 2007 John Wiley & Sons, Ltd.
Dynamic binding capacity of plasmid DNA in histidine–agarose chromatography
Authors: Sousa F. , Prazeres D. M. F. , Queiroz J. A.
Published: May 2007

The use of histidine–agarose chromatography in the purification of supercoiled (sc) plasmid DNA (pDNA) from Escherichia coli lysates has been reported recently. In the current work we describe a set of breakthrough experiments which were designed to study the effect of parameters such as flow‐rate, temperature, concentration and conformation on the dynamic binding capacity of pDNA to the histidine support. One of the most striking results shows that the dynamic binding capacity for sc pDNA decreases linearly from 250.8 to 192.0 µg sc pDNA/mL when the temperature is varied from 5 to 24°C. This behaviour was attributed to temperature‐induced, pre‐denaturation conformational changes which promote the removal of negative superhelical turns in sc pDNA molecules and decrease the interaction of DNA bases with the histidine ligands. The capacity for sc pDNA was highly improved when using feeds with higher pDNA concentrations, a phenomenon which was attributed to the fact that pDNA molecules in more concentrated solutions are significantly compressed. A maximum capacity of 530.0 µg pDNA/mL gel was obtained when using a 125 µg/mL pDNA feed at 1 mL/min and 5°C, a figure which is comparable to the plasmid capacity values published for other chromatographic supports. Finally, a more than 2‐fold increase in capacity was obtained when changing from open circular to sc pDNA solutions. Overall, the results obtained provide valuable information for the future development and implementation of histidine chromatography in the process scale purification of pDNA. Copyright © 2007 John Wiley & Sons, Ltd.
Quantitative gas chromatography/time‐of‐flight mass spectrometry: a review
Authors: Williamson Leah N. , Bartlett Michael G.
Published: May 2007

Time‐of‐flight (TOF) instruments have recently gained popularity in quantitative analyses. Normally, TOF mass spectrometers are used for accurate mass measurements for empirical formula verification. However, over the past decade, they have been used quantitatively as well. Because of the fast separations and narrow peaks that result from gas chromatography separations, scanning mass spectrometers are not ideal detectors. TOF mass spectrometers, however, have the ability to collect spectra at a faster rate. Two‐dimensional gas chromatography has also been introduced to further resolve peaks from complex matrices. Two‐dimensional gas chromatography results in a faster separation as well as narrower peaks. This paper reviews the methods currently in the literature for the quantitation of compounds using one‐ and two‐dimensional gas chromatography and TOF mass spectrometry detection. Copyright © 2007 John Wiley & Sons, Ltd.
Searching for Stable, Five‐Coordinate Aquated Al(III) Species. Water Exchange Mechanism and Effect of pH.
Authors: Hanauer Hans , Puchta Ralph , Clark Timothy , van Eldik Rudi
Published: May 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Ta3AlC2 and Ta4AlC3 — Single‐Crystal Investigations of Two New Ternary Carbides of Tantalum Synthesized by the Molten Metal Technique.
Authors: Etzkorn Johannes , Ade Martin , Hillebrecht Harald
Published: May 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
The Metal‐Rich Palladium Chalcogenides Pd2MCh2 (M: Fe, Co, Ni; Ch: Se, Te): Crystal Structure and Topology of the Electron Density.
Authors: Pocha Regina , Loehnert Catrin , Johrendt Dirk
Published: May 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Structures and Physical Properties of New Semiconducting Gold and Copper Polytellurides: Ba7Au2Te14 and Ba6.76Cu2.42Te14.
Authors: Cui Yanjie , Assoud Abdeljalil , Xu Jianxiao , Kleinke Holger
Published: May 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Syntheses and X‐Ray Diffraction, Photochemical, and Optical Characterization of Cu2SixSn1‐xS3 (0.4 ≤ x ≤ 0.6) for Photovoltaic Applications.
Authors: Lafond A. , Cody J. A. , Souilah M. , Guillot‐Deudon C. , Kiebach R. , Bensch W.
Published: May 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Nanoparticles of Superconducting γ‐Mo2N and δ‐MoN.
Authors: Gomathi A. , Sundaresan A. , Rao C. N. R.
Published: May 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Neutron Diffraction and X‐Ray Absorption Study of Ag5Pb2O6.
Authors: Yoshii K. , Mizumaki M. , Kato K. , Uruga T. , Abe H. , Nakamura A. , Shimojo Y. , Ishii Y. , Morii Y.
Published: May 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Neutron Diffraction and Theoretical DFT Studies of Two Dimensional Molecular‐Based Magnet K2[Mn(H2O)2]3 [Mo(CN)7]2×6H2O.
Authors: Gillon Beatrice , Goujon Antoine , Willemin Stephanie , Larionova Joulia , Desplanches Cedric , Ruiz Eliseo , Andre Gilles , Stride John A. , Guerin Christian
Published: May 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Integrated Experimental—Theoretical Investigation of the Na—Li—Al—H System.
Authors: Opalka Susanne M. , Loevvik Ole M. , Brinks Hendrik W. , Saxe Paul W. , Hauback Bjoern C.
Published: May 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Hydrothermal Synthesis of Fine NaTaO3 Powder as a Highly Efficient Photocatalyst for Overall Water Splitting.
Authors: Lee Yungi , Watanabe Tomoaki , Takata Tsuyoshi , Hara Michikazu , Yoshimura Masahiro , Domen Kazunari
Published: May 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthesis of NaAlH4‐Based Hydrogen Storage Material Using Milling under Low Pressure Hydrogen Atmosphere.
Authors: Eigen Nico , Kunowsky Mirko , Klassen Thomas , Bormann Ruediger
Published: May 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthesis and Crystallization of Hexagonal Boron Nitride in Liquid Sodium Amide.
Authors: Gu Yunle , Zheng Mingtao , Xu Zilin , Liu Yingliang
Published: May 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Low‐Temperature Flux Syntheses and Characterizations of Two 1‐D Anhydrous Borophosphates: Na3B6PO13 and Na3BP2O8.
Authors: Xiong Ding‐Bang , Chen Hao‐Hong , Yang Xin‐Xin , Zhao Jing‐Tai
Published: May 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Novel Vanadium(IV) Oxyfluorides with “Spin‐Ladder”‐Like Structures, and Their Relationship to (VO)2P2O7.
Authors: Aldous David W. , Goff Richard J. , Attfield J. Paul , Lightfoot Philip
Published: May 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Mild Hydrothermal Synthesis and Magnetic Properties of the Manganates Pr1‐xCaxMnO3.
Authors: Chen Yan , Yuan Hongming , Tian Ge , Zhang Ganghua , Feng Shouhua
Published: May 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Two Unprecedented Inorganic—Organic Boxlike and Chainlike Hybrids Based on Arsenic—Vanadium Clusters Linked by Nickel Complexes.
Authors: Qi Yanfei , Li Yangguang , Wang Enbo , Jin Hua , Zhang Zhiming , Wang Xinglong , Chang Song
Published: May 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Silver Iodobismuthates: Syntheses, Structures, Properties, and Theoretical Studies of [Bi2Ag2I102‐]n and [Bi4Ag2I162‐]n.
Authors: Chai Wen‐Xiang , Wu Li‐Ming , Li Jun‐Qian , Chen Ling
Published: May 2007

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.