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作者：GOOD, IJ; LEWIS, BC; GASKINS, RA; HOWELL, LW
摘要：Moran (1951) proposed an approximate formula for the likelihood of the size of an animal population when the removal method is used. An exact formula was obtained for the likelihood based on an assumption of proportional trapping of animals. The formula is ill conditioned and requires extremely high precision arithmetic for its numerical evaluation. A form of minimum chi-squared or weighted least-squares method is given for estimating population size. For this method the calculations are not b...
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作者：LEE, SY
摘要：In covariance structure analysis, the method of weighted least squares for estimating parameters subject to functional constraints is developed. Statistical properties of the estimator are studied and a goodness-of-fit statistic is presented. Based on the penalty function technique, an algorithm is developed. This algorithm is able to produce the constrained weighted least squares estimator and the constrained maximum likelihood estimator if an appropriate weight matrix is chosen iteratively. ...
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作者：SCOTT, DW
摘要：The formula for the optimal histogram bin width is derived which asymptotically minimizes the integrated mean squared error. Monte Carlo methods are used to verify the usefulness of this formula for small samples. A data-based procedure for choosing the bin width parameter is proposed, which assumes a Gaussian reference standard and requires only the sample size and an estimate of the standard deviation. The sensitivity of the procedure is investigated using several probability models which vi...
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作者：AITCHISON, J; LAUDER, IJ
摘要：The fact that diagnostic measurements are often subject to error, with the extent of the imprecision varying from case to case, is largely ignored in current methodology of statistical diagnosis. Models taking full account of such imprecision are proposed and the necessary methods developed. A useful combination of a cumulative-normal diagnostic model with a normal error model is studied. Applications to 2 specific medical diagnostic problems illustrate the differing extents of the misrepresen...
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作者：HIROTSU, C
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作者：LININGER, L; GAIL, MH; GREEN, SB; BYAR, DP
作者单位：National Institutes of Health (NIH) - USA; NIH National Cancer Institute (NCI)
摘要：Monte Carlo experiments investigated the small sample behavior of 4 tests used to analyze stratified censored human survival data. The size of the generalized Gehan and Mantel-Haenszel statistics were near nominal level .alpha. = 0.05. The observed size of the Cox partial likelihood ratio statistic was typically 0.065 for fewer than 32 observations per stratum and fell to near nominal levels for larger sample sizes. The continuity corrected Mantel-Haenszel statistic was consistently conservati...
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作者：PEDERSEN, BV
摘要：Conditional density and distribution functions were approximated by the mixed Edgeworth-saddlepoint expansion. This technique is described, and its use and character are illustrated by 3 examples [time-dependent Poisson process, comparing rates of Poisson processes and truncated normal density for survival data] concerning miscellaneous exponential families of order 2.
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作者：ROSNER, B
摘要：Maximum likelihood was used to estimate a mother-child correlation, .rho.ms, when there are a variable number of offspring per family. The technique is iterative and uses standard Newton-Raphson procedures to facilitate convergence. A comparison is made using Monte Carlo methods between the maximum likelihood estimator and other more traditional estimators of interclass correlations. The maximum likelihood estimator is roughly equivalent in mean squared error to the pairwise estimator.
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作者：PRENTICE, RL; PYKE, R
作者单位：University of Washington; University of Washington Seattle
摘要：The probability of disease development in a defined time period is described by a log regression model. A model for the regression variable, given disease status, is induced and is applied to case control data. The odds ratio estimators and the asymptotic variance matrices may be obtained by applying the original log regression model to the case control study as if the data are obtained in a prospective study. This result gives a flexible and convenient method of analysis for a range of case c...
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作者：BRETH, M
摘要：Bayesian confidence bands for a distribution function are converted into confidence intervals for specified population quantiles and also for the mean. Bayesian tolerance limits are similarly constructed.
