bluuebunny/crossref_metadata_2025_split huggingface dataset:
An English/Spanish safety climate scale for construction workers
Authors: Jorgensen Emile , Sokas Rosemary K. , Nickels Leslie , Gao Weihua , Gittleman Janie L. 
Published: May 2007

AbstractBackgroundWorkers in the construction trades experience high rates of traumatic injury. An increasing number of workers in this industry speak only Spanish, including members of construction trade unions. This brief communication reports a dual language safety climate scale developed during a larger training intervention study.MethodsConstruction workers in two unions self‐completed a previously validated 6‐item safety climate scale modified for the construction trades. A seventh item was developed midway through the study and incorporated into the version completed by half of the respondents. For one union with a sizeable number of Spanish‐speaking members, a dual‐language (Spanish/English) version was administered. Follow‐up telephone interviews conducted 3 months after the self‐completed survey also included the safety climate scale.ResultsCronbach's coefficient alpha was 0.85 for the 6‐item scale and 0.85 for the 7‐item scale. Similar coefficient alpha scores were found for the subgroup of Spanish‐speakers on the 6‐ and 7‐item scales. Spanish speakers with low education were less likely to respond to the scale when self‐completing but not when it was administered by telephone in Spanish.ConclusionThis safety climate scale elicits consistent and reliable response from unionized construction workers when administered in English or in Spanish. Spanish literacy may be a consideration for the use of this scale among foreign‐born Hispanic workers. Am. J. Ind. Med. 50:438–442, 2007. © 2007 Wiley‐Liss, Inc.
Evidence for bronze age cannibalism in El Mirador Cave (Sierra de Atapuerca, Burgos, Spain)
Authors: Cáceres Isabel , Lozano Marina , Saladié Palmira 
Published: May 2007

AbstractDuring excavations of the Bronze Age levels at El Mirador Cave, a hole containing human remains was found. Taphonomic analysis revealed the existence of cutmarks, human toothmarks, cooking damage, and deliberate breakage in most of the remains recovered, suggesting a clear case of gastronomic cannibalism. The piled distribution of the remains, the uneven skeletal representation, and the chronological difference between the pit and the remains suggest that these bones were subsequently buried by a human group that inhabited into the cave later in time. Evidence of gastronomic cannibalism has already been documented in Gran Dolina, another site in the Sierra de Atapuerca, on remains of Homo antecessor with an age of 800 ky (Fernández‐Jalvo et al.: Science 271 (1996) 277–278; Fernández‐Jalvo et al.: J Hum Evol 37 (1999) 591–622). Am J Phys Anthropol, 2007. © 2007 Wiley‐Liss, Inc.
Elektrophile Aktivierung von Alkenen mit Platin(II): sehr viel mehr als eine langsame Variante von Palladium(II)
Authors: Chianese Anthony R. , Lee Stephen J. , Gagné Michel R. 
Published: May 2007

AbstractDie elektrophile Aktivierung von Alkenen durch Übergangsmetallkatalysatoren ist die erste Reaktionsstufe bei einer Vielzahl von katalytischen Prozessen. Das bekannteste Metall für diesen Zweck ist Palladium, in jüngerer Zeit konnten aber auch die besonderen Eigenschaften des verwandten Platins (starke Metall‐Ligand‐Bindungen, langsame Substitutionen) genutzt werden, um häufig komplementäre Umsetzungen zu entwickeln, die durch Addition von protischen Kohlenstoff‐, Stickstoff‐, Sauerstoff‐, Phosphor‐ sowie Alken‐ und Aren‐Nucleophilen an eine CC‐Bindung eingeleitet werden. Die Umsetzungen mit Platinreagentien zeigen oft sehr charakteristische Reaktivitätsprofile, die zu gänzlich neuen Reaktionsprodukten führen. Dieser Aufsatz gibt einen Überblick über Platin‐katalysierte elektrophile Aktivierungen von Alkenen, wobei die Beschreibung von Reaktionsmechanismen, die Unterschiede zwischen Platin‐ und Palladiumkatalysatoren und die Aussichten für die Entwicklung neuer Systeme im Mittelpunkt stehen.
Negative binomial version of the Lee–Carter model for mortality forecasting
Authors: Delwarde Antoine , Denuit Michel , Partrat Christian 
Published: May 2007

AbstractMortality improvements pose a challenge for the planning of public retirement systems as well as for the private life annuities business. For public policy, as well as for the management of financial institutions, it is important to forecast future mortality rates. Standard models for mortality forecasting assume that the force of mortality at age x in calendar year t is of the form exp(αx + βxκt). The log of the time series of age‐specific death rates is thus expressed as the sum of an age‐specific component αx that is independent of time and another component that is the product of a time‐varying parameter κt reflecting the general level of mortality, and an age‐specific component βx that represents how rapidly or slowly mortality at each age varies when the general level of mortality changes. The parameters are usually estimated via singular value decomposition or via maximum likelihood in a binomial or Poisson regression model. This paper demonstrates that it is possible to take into account the overdispersion present in the mortality data by estimating the parameter in a negative binomial regression model. Copyright © 2007 John Wiley & Sons, Ltd.
Designs for Discrimination Between Bivariate Binary Response Models
Authors: Yanagisawa Yukto 
Published: May 2007

AbstractWe propose a test statistic for discrimination between alternative bivariate binary response models and the optimal design procedure which is an extension of T‐optimality. Under certain conditions we prove that the maximum value of the power can be‐obtained when the degrees of freedom of the test statistic is one. The conclusion is the same as that in discrimination between alternative univariate separate models. However the test statistics are different.
A Simple Method to Obtain all the Sample‐Values and their Probabilities of the Wald‐Wolfowitz Test Statistics in the Existence of Ties
Authors: Yassouridis A. 
Published: May 2007

AbstractIn order to carry out non‐conservative tests in the general two‐sample problem with ties, we want to know all possible sample‐values of the used test statistics and their occurrence probabilities as well. But this knowledge can be acquired only after very protracted attempts. In the present paper we depict a simple technique for obtaining that without any exertion in the case of the Wald‐Wolfowitz test statistic. With that, we then are able to lead the Wald‐Wolfowitz test easily and effortlessly in any manner conservative or non‐conservative and in the existence of any number and any length of ties.
Comparisons of Some Chi‐squared Tests for the Test of Independence in Sparse Two‐Way Contingency Tables
Authors: Lawal H. B. , Uptong G. J. G. 
Published: May 2007

AbstractWe consider in this paper, the behaviour of a class of the CRESSIE READ (1984) power divergence test statistics indexed by parameter λ ‐I(λ), with the modifiedX2test statistics (LU) proposed by LAWAL and UPTON (1984), for sparse contingency tables ranging from the 3×3 to the 10×10. We present a sample of our results here. The results indicate that the LU test out‐performs either the Cressie‐Read suggested testI(2/3) or the Pearson's test ‐I(1). Our results further show that the modification to the likelihood ratio test [Y2=I'(0)] proposed by WILLIAMS (1976) performs like the parentY2test, very poorly compared with either theI(2/3),X2or the LU test statistics.Power results also indicate that the powers of the LU test are in all cases considered in this study slightly higher than those ofX2andI(2/3) tests. The LU test is therefore strongly recommended for use with sparse two‐way contingency tables because in all of the cases considered, none of the other test statistics consistently out‐performs the LU test with respect to attained α level or power.
Boolean Models: Maximum Likelihood Estimation from Circular Clumps
Authors: Ayala G. , Ferrándiz J. , Montes F. 
Published: May 2007

AbstractThis paper deals with the problem of making inferences on the maximum radius and the intensity of the Poisson point process associated to a Boolean Model of circular primary grains with uniformly distributed random radii. The only sample information used is observed radii of circular clumps (DUPAC, 1980). The behaviour of maximum likelihood estimation has been evaluated by means of Monte Carlo methods.
Choice of Scale and Asymmetric Logistic Models
Authors: Hauck Walter W. 
Published: May 2007

AbstractIn recent years, a number of authors have proposed generalizations to the binomial logistic model. These proposals were motivated, in part, by the claimed inability of the logistic model to fit asymmetric data, that is, data that does not follow a symmetric S‐shaped curve. In this note, it is demonstrated that by changing the scale of the independent variable(s), the logistic model can fit asymmetric data. Logistic models are fit to data from BLISS (1935) that had been used as an example by three of the authors; the logistic models fit Bliss' data as well as the proposed alternative models. In a general sense, these data serve as an example of the need to consider the appropriate choice of scale of the independent variables in logistic analysis.
On Edge‐Corrected Kernel‐Based Pair‐Correlation Function Estimators for Point Processes
Authors: Doguwa Sani I. 
Published: May 2007

AbstractEdge‐corrected kernel‐based estimators are proposed for the pair‐correlation functiong(t). These estimators are compared by simulation methods with the existing edge‐corrected estimator suggested by FIKSEL (1988, Statistics, 19, 67–75). The results of the simulation study suggests that all the edge‐corrected estimators are almost unbiased. Furthermore, the estimators proposed in this paper have a smaller mean squared error than the existing alternative. Finally, the catoptrophorus semipalmatus nesting pattern is explored.
Simultaneous Statistical Inference Concerning the Standardized Mortality Ratios (SMB) of Several Strata in an Epidemiologic Study
Authors: Rao B. Raja , Marsh Gary M. 
Published: May 2007

AbstractIn the present paper, simultaneous prediction intervals are constructed for some mortality measures involving real data in a recent retrospective epidemiologic study of a cohort of man‐made mineral fiber workers. The object is to compare a test population with a standard population in which the workers are exposed to several levels (say K) of a suspected carcinogen and the number of deaths in the K exposure groups are recorded. The SMR is chosen as a mortality measure for this comparison. If the total number of deaths d. in the entire study is known, the number of deaths in the various strata become dependent random variables. Using univariate statistical procedures to test the significance of the individual SMR's is inappropriate and may give misleading conclusions. The present paper shows how to test the simultaneous statistical significance of the SMR's of the K exposure groups, i.e., to test the simultaneous null hypothesis Ho : E(SMR1) = E(SMR2) =…E(SMRk) = 100. If the null hypothesis Ho is rejected, it is shown how to identify the SMR (or the SMR's) which contributed to the rejection of Ho. The power function of such a test is also constructed for some simple and useful alternative hypotheses.
Robustness of the Probability of Correct Selection Against Deviations from the Assumption of a Common Known Variance
Authors: Driessen Stefan , Van Der Laan Paul , Van Putten Brand 
Published: May 2007

AbstractIn this paper we investigate the robustness of the probability of correct selection against departures from the assumption of a common known variance for the Indifference Zone approach (cf. BECHHOFER(1954)), as well as for the Subset Selection approach (cf. GUPTA(1956, 1965)) in the case of Normal populations. It appears that there is a serious lack of robustness in the sense that the actual lower bound of the probability of correct selection can be considerably smaller than the pretended lower boundP*of the probability of correct selection based on the assumption of a common known variance, ifP*is taken 0.75, 0.90, 0.95 and 0.99, respectively.
Sequential Sampling Estimation for Finite Populations ofN = nrObjects
Authors: Arnold B. C. , Groeneveld R. A. 
Published: May 2007

AbstractRandom sampling from a finite population of sizeN = nr(rknown) is considered. The statistic observed isT, the number of observations required until thekth set of sizelfrom thensets ofris obtained. An asymptotically unbiased estimator ofnis obtained together with its approximate variance. Recommendations are made for choices ofrandl, based on the large sample expectation ofT. An application in archeology to the estimation of the number of individuals originally present based on multiple bone counts is considered.
Sampling Methodology for a Boat‐Fishing Survey Design for Hawaii
Authors: Sen A. R. 
Published: May 2007

AbstractThe primary objective of this study is to develop a workable and cost‐effective sampling plan for obtaining reliable estimates of annual catch made by recreational boat‐fishermen in Hawaii and of efforts expended by fishing method for some of the important management species.Sampling methodology will be developed in an intercept survey through interview of boat fishermen who were intercepted at sampled ports on the island of Oahu for estimating:(i) number of fishing trips at a particular site or port during a specified time period,(ii) total catch (weight) and also catch for individual species by fishing method,(iii) total time spent at sea e.g., boat hours by fishing method.The sampling strategy will take into account the need to obtain reliable and more specific information to meet particular fisheries management goals. Other research problems which may have important management implications and bearing on the sampling design will also be considered. Finally, sample size will be derived to estimate catch, effort and catch per unit effort at a port with a pre‐assigned level of accuracy.
Further Results on Minimax Designs to Estimate the Slope of a Response Surface
Authors: Huda Shahariar 
Published: May 2007

AbstractThe problem considered is polynomial regression and minimization of the variance of estimated slope maximized over all points in the region of interest when the design region and region of interest are hyperspheres with a common centre. Optimal designs under the criterion are derived for the second‐order model. Method of deriving optimal designs for the third‐order model is indicated and some limiting results on these designs are obtained.
Accuracy of Asymptotic Interval Estimation Methods for Comparing Two Risks
Authors: Nurminen M. , Nurminen T. 
Published: May 2007

AbstractIn 1985, Miettinen and Nurminen proposed asymptotic likelihood‐based methods for the interval estimation of risk differences, risk ratios and risk‐odds ratios. In the present study, with the use of simulated coverage probabilities in small samples, the actual confidence coefficients of all three of the proposed interval estimates for unstratified data were determined in a comparison with the usual ones. Rated against the 95% coverage probability, the likelihood methods that use restricted maximum likelihood estimators accurately attained the nominal level. The recommended limits also apportioned fairly equal error rates for both tails. The customary intervals performed less successfully. For simple risk differences the estimated confidence probabilities failed to reach the 95% level. For the differences in log‐transformed risks, the tail probabilities of the confidence intervals were disparately allocated, and the method was occasionally incomputable. For the difference in logit‐transformed risks, the uncorrected Woolf intervals were at times fallible and somewhat conservative in comparison to the likelihood ratio‐based intervals. Modification of the conservative Cornfield limits for the risk‐odds ratio greatly improved the accuracy of the likelihood score‐based procedure. With sparse‐stratified data the likelihood score approach produced a biased estimate of the risk‐odds ratio, which for matched pairs equals the square of the exact, conditional maximum likelihood estimate.
The Sequential Estimation of Quantal Response Curves for Small Sample Sizes
Authors: Wharton Robert M. , Srinivasan R. 
Published: May 2007

AbstractAn approach to the sequential estimation of the location and scale‐parameters of a logistic response curve using small sample sizes is discussed. The experimental design employed is a variation of Dixon's Up‐Down method with variable step size. Modified maximum likelihood estimates for the location and scale parameters are used in conjunction with this design. The effectiveness of the new estimation procedure and a comparison of this experimental design with some standard alternative designs are examined using Monte Carlo simulation.
A Single Compartment Quantal Response Model with an Inspection Process
Authors: Horng Chia‐Tsung , Huang Wen‐Jang , Lo Huang Mong‐Na 
Published: May 2007

AbstractIn a single compartment quantal response model, besides the input and release processes, an inspection process, assumed to be independent of the input and release processes, is considered. Each time when a release occurs, we assume the amount of release is randomly proportional to the amount present and the proportional rates form a sequence of independent and identically distributed random variables with support on [0, 1]. The input policy we consider is a modification of (s, S) input policy in the inventory model. More precisely, let 0 ≦s2 ≦s1 ≦s ≦ S, if after a release, the amount of the drug in subject's body is less than a level s2 which is small enough, then there will be an input immediately with probability 1 — p and no more inputs thereafter with probability p, also there will be an input immediately if the dose level is in the interval [s2, s1). If the dose level is in the interval [s1, s) there will be no input unless the inspector arrives. On the other hand, if the dose level is greater than or equal to s, then there will be no input. We consider a stochastic model as described above, and obtain the expressions for some quantities of interest. A Monte Carlo study has also been carried out to demonstrate some behaviors of our quantal response process.
On Nonrandom Mating Systems for Attaining Hardy‐Weinberg Equilibrium
Authors: Tai J. J. 
Published: May 2007

AbstractLI (1988) showed that random mating is a sufficient, not a necessary condition for the Hardy‐Weinberg principle. A nonrandom mating population that behaves like a random mating population is thus called a ‘pseudo‐random mating population’ by him. The pseudo‐random mating system studied by him has been focused on those populations in which the parental generation is in Hardy‐Weinberg proportions. In other words, the mating type frequency deviations from random mating for each parental genotype add up to zero. In this article these restrictions are relaxed and new pseudo‐random mating systems that immediately yield Hardy‐Weinberg offspring are also obtained. This is possible because reciprocal crosses have identical segregation probabilities for an autosomal locus, and the manipulation of the combined frequency of reciprocal crosses does not change the gene frequency of the population. A comparison of these new patterns with that of Li is given in the Discussion.
First Passage Time Models for Prediction of Developmental Stages
Authors: Jensen Jens Erik , Rudemo Mats 
Published: May 2007

AbstractThe problem of predicting the date of a developmental stage for plants or animals is formulated as a first passage time problem for a random process, e.g. accumulated degree‐days. By a suitable embedding in a continuous time model the likelihood becomes a smooth function of the parameters, which may be estimated by use of the maximum likelihood method. A set of data on waiting times from sowing to heading for spring barley is analysed. For data of this type we suggest models with variance components corresponding to stations and years. Modifications to take into account variables in addition to temperature, e.g. day length, soil properties and variety effects are briefly discussed. The transform both sides technique of CARROLL and RUPPERT (1984) is used to stabilize the variance and to achieve approximate normality of the residuals.
On Discrimination of (Stationary) Stochastic Processes
Authors: Wernecke K.‐D. , Kalb G. , Stuerzebecher E. 
Published: May 2007

AbstractAn essential basis of medical diagnosis are biopotentials obtained from the body‐surface of the patients.If these time‐functions are to serve for computer‐aided diagnostics (using discrimination procedures) the known methods fail because of the existing small sample sizes for a large number of features (amplitudes).In the paper a method is given allowing discrimination of biopotentials also with such an extreme ratio of the number of features to the sample size.Furthermore, univariate tests are provided, enabling a decision to be made on whether the possibly arising distinctions may be attached to the mean values and/or the spectra of the underlying potentials.Clinical applications from the field of otolngical diagnostics demonstrate the usefulness of the described methods and show in particular their superiority compared with the known linear discriminance analysis.
On Analysis of Proportions in Tables with Spoiled Data
Authors: Lachenbruch P. A. 
Published: May 2007

AbstractThis paper discusses analysis of dispersion tests in tables with spoiled data, that is, where some cells are missing. BENNETT (1987) gave a method for estimating the missing cells in a two‐way table and illustrated it with a simple example. This paper uses GLIM to estimate the models and indicates that the General Linear Model performs the computations without need to estimate the missing values. The binomial error model also may be used for this problem, and is the more natural approach to the problem.
Applying Canonical Analysis to a Kind of Generalized Regression
Authors: Liu Chui‐Yu 
Published: May 2007

AbstractThis paper is concerned with the generalized model E(φ(Y)! X) =φ(X) involving the transformations on both the predictor vector X and the response variable Y. For this purpose, Taylor expansions and canonical analysis are applied. For optimizing the expansions, it is shown by a simulation study that not only prediction error, the combination of model error and noise error, is an important index, but the distribution of the residuals and the t‐values of the coefficients also must be considered. Furthermore, the results of penicillin titrition show that the practical situations often need to be considered in selecting an appropriate model for a real‐life problem.
Testing Equality of Means in the Presence of Correlation and Missing Data
Authors: Bhoj Dinesh S. 
Published: May 2007

AbstractA statistic, derived from the combination of two dependent tests, is proposed for testing the hypothesis of equality of the means of a bivariate normal distribution with unknown common variance and correlation coefficient when observations are missing on one or both variates. The null distribution of the statistic is approximated by a well‐known distribution. The empirical powers of the statistic are computed and compared with some of the known statistics. The comparisons support the use of the proposed test.
Generalized Rank Transformations for Tests of Survival
Authors: Schemper Michael 
Published: May 2007

AbstractThe asymptotic equivalence of nonparametric tests and parametric tests based on rank‐transformed data (CONOVER and IMAN, 1981) can be extended to the case of censoring. This paper presents generalized rank transformations for analyses of censored data, of interval‐censored data and of survival data with uncertain causes of death. A Monte Carlo study and an analysis of leukemia remission times demonstrate excellent agreement of suggested procedures with GEHAN'S (1965) and PRENTICE'S (1978) tests.