Biometrika

最新文章

• EFFICIENT CONDITIONAL TESTS FOR MIXTURE EXPERIMENTS WITH APPLICATIONS TO THE BIRTH AND BRANCHING-PROCESSES AI翻译
  作者：BASAWA, IV
  摘要：Conditional tests, which are efficient in the sense of being uniformly most powerful unbiased for any sample size and are also asymptotically efficient with reference to a relevant likelihood in the sense of maximizing asymptotic power at alternatives converging to the null hypothesis, are derived for mixture experiments involving dependent observations. As simple applications efficient tests in birth processes, branching processes, stable additive processes, etc., are derived.
• ON GOODNESS OF FIT OF TIME-SERIES MODELS - AN APPLICATION OF HIGHER-ORDER CROSSINGS AI翻译
  作者：KEDEM, B; SLUD, E
  摘要：A relation between the graphical appearance of a stationary time series and its autocorrelations is discussed. The use of counts of visual features termed higher order crossings is proposed in testing goodness of fit of hypothesized models against very general alternatives. Attention is focused on a specific example of a new type of nonparametric test statistic arising from iterative feature extraction procedures called extractors. The statistic is compared with Box and Pierce''s portmanteau Q...
• THE INFECTIOUSNESS OF A DISEASE WITHIN HOUSEHOLDS AI翻译
  作者：BECKER, N
  摘要：The potential that an infective has for infecting a given susceptible from the same household is quantified as a random variable depending on the duration of the infectious period, the severity of the illness and the mobility of the infective. Procedures for making inference about the mean value and the variance of this potential are proposed. The proposed analysis makes it possible to test whether infectives display significant differences in their infectiousness. The methods apply to disease...
• A BAYESIAN-ANALYSIS OF MULTIPLE-RECAPTURE SAMPLING FOR A CLOSED POPULATION AI翻译
  作者：CASTLEDINE, BJ
  作者单位：University of Leicester
  摘要：Inferences from a Bayesian viewpoint about the size of a closed animal [sunfish] population from data obtained by a multiple-recapture sampling scheme were considered. The method developed enables prior information about the population size and the catch probabilities to be utilized to produce improvements in certain cases on ordinary maximum likelihood methods. Several ways of expressing such prior information are explored and a practical example of the uses of these ways is given. The main r...
• INITIAL SIZE ESTIMATION FOR THE LINEAR PURE DEATH PROCESS AI翻译
  作者：GOUDIE, IBJ; GOLDIE, CM
  作者单位：University of Sussex
  摘要：Consider a linear pure death process in which the common death rate and the initial size n of the population are both unknown. An estimate of n is required, based on the observed times of the 1st j deaths, i.e., with censored sampling. The only reliable nonBayesian method is to use interval estimates, for all the standard point estimation techniques are liable to fail. Appropriate interval estimators are derived and discussed. The corresponding truncated sampling model is considered.
• SEQUENTIAL ESTIMATION IN 2-ARMED EXPONENTIAL CLINICAL-TRIALS AI翻译
  作者：HAYRE, LS; TURNBULL, BW
  作者单位：Pennsylvania Commonwealth System of Higher Education (PCSHE); Temple University; Cornell University
  摘要：Asymptotically optimal sequential procedures are developed for point and interval estimation of the difference and ratio of the means of 2 experimental populations. This is done in a clinical trial setting in which the responses are exponentially distributed survival times and are subject to censoring. The usual situation in which observations are immediate is treated as a special case. Some simulation results are given for moderate sample sizes [i.e., patients, treatments and death].
• EFFICIENCY OF ESTIMATING EQUATIONS AND THE USE OF PIVOTS AI翻译
  作者：MORTON, R
  作者单位：Commonwealth Scientific & Industrial Research Organisation (CSIRO)
  摘要：Methods are proposed for deriving unbiased estimating equations for the parameters of interest in a statistical model which includes further incidental or nuisance parameters. Pivot-like quantities eliminate the dependence on the incidental parameters and functions are derived which give estimating equations which are most efficient in a certain sense. These equations involve the incidental parameters, which are then replaced by estimators. The methods overcome some of the difficulties encount...
• THE GRAPHICAL EVALUATION OF EXPLANATORY VARIABLES IN PROPORTIONAL HAZARD REGRESSION-MODELS AI翻译
  作者：LAGAKOS, SW
  作者单位：Harvard University; Harvard Medical School; Harvard University Medical Affiliates; Dana-Farber Cancer Institute
  摘要：A graphical technique for assessing explanatory variables in Cox''s proportional hazards regression model is examined. The method arises from consideration of the cumulative hazard transformation and the partial likelihood score function, and consists of permuting the observed rank statistic to account for the effects of explanatory variables fitted to the model. An example is provided [i.e., survival times, from date of transplantation, for patients in a heart transplant study].
• LATENT VARIABLE MODELS FOR STATISTICAL DIAGNOSIS AI翻译
  作者：LAUDER, IJ
  摘要：A class of statistical models is derived for the problem of differential diagnosis between several types of disease. The performance of models for differential diagnosis between 3 and 4 types is assessed on clinical data.
• A TEST OF FIT IN TIME-SERIES MODELS AI翻译
  作者：MILHOJ, A
  摘要：A goodness-of-fit test statistic for time series models is presented, and its asymptotic distribution, even when parameters are estimated, is derived. The statistic is a frequency domain analog of the Box-Pierce portmanteau statistic. The symptotic power of the test is found and compared to the empirical power of the portmanteau test. The small sample properties are investigated by Monte-Carlo methods.