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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：KRZANOWSKI, WJ
摘要：Suitable linear transformations for preliminary data analysis are available when data consist solely of continuous variables or solely of binary variables. When mixtures of variables are observed, neither technique provides a satisfactory procedure. Some linear transformations for such data are therefore proposed. The aim of the transformations is to simplify structure. An additional motivation comes from the field of discriminant analysis, where it is hoped that dimensionality can be reduced ...
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作者：FINCH, PD
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作者：GILL, CA; JOANES, DN
摘要：Methods of estimating Shannon''s information measure and the sampling properties of those estimates are considered. A Bayesian approach was used to suggest 2 possible classes of estimators, and their properties are compared with those of the usual Shannon measure of diversity. Particular attention is given to comparisons involving the MacArthur model of species abundances.
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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：KALBFLEISCH, JD; MACKAY, RJ
摘要：Williams and Lagakos (1977) considered a class of models for censored [human] survival data in which the censoring and survival mechanisms are related by what is called a constant-sum condition. The constant-sum condition is equivalent to a simple relationship between hazard functions.
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作者：MARTIN, RJ
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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.
