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作者：RUBIN, DB; THOMAS, N
作者单位：Educational Testing Service (ETS)
摘要：Matched sampling is a standard technique for controlling bias in observational studies due to specific covariates. Since Rosenbaum & Rubin (1983), multivariate matching methods based on estimated propensity scores have been used with increasing frequency in medical, educational, and sociological applications. We obtain analytic expressions for the effect of matching using linear propensity score methods with normal distributions. These expressions cover cases where the propensity score is eith...
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作者：CHIU, ST
摘要：To select a proper bandwidth is a critical step in kernel density estimation. It is well known that the bandwidth selected by cross-validation has a large variability. This difficulty limits the applicability of cross-validation. To reduce the variability, we suggested modifying the sample characteristic function beyond some cut-off frequency in estimating the bias term of the mean integrated squared error. It is proposed to select the cut-off frequency by a generalization of cross-validation....
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作者：ONEILL, TJ
摘要：We call a classification procedure non-Bayes if it does not converge to the Bayes classification procedure. An asymptotic expansion is found for the expected error rate of such a classification rule. This is used to compare the estimates of Fisher's linear discriminant rule, F, and the quadratic discriminant rule, Q, under departures from the equal variance matrices assumption. It is found that F is quite robust to departures from the equal variances assumption.
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作者：LI, WK
摘要：The asymptotic distribution of residual autocorrelations for some very general nonlinear time series models is derived. This includes the important class of threshold models. Consequently more accurate standard errors for residual autocorrelations can be obtained facilitating model diagnostic checkings in many situations. A small simulation result applying the methodology to threshold models is reported.
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作者：LLOYD, CJ
摘要：An estimation method of Lloyd & Yip (1991), based on martingales and the assumption of beta distributed capture probabilities, is modified to improve its performance for all but highly heterogeneous populations. This estimator is compared to the jackknife estimator by simulation under both beta and non-beta conditions. Some expressions for standard error are developed but found to behave poorly for realistic sample sizes. Bootstrap estimates of standard error appear superior but do not lead to...
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作者：WILSON, RM; COLLINS, MF
摘要：One way in which a capture-recapture experiment can be designed is to count each capture occasion as a separate sample, and tally the number of individuals caught once, twice, and so on. This paper discusses the estimators currently used for this type of experiment, and suggests some new ones. Each of the estimators is categorized by its derivation. Following this, their properties are discussed, particularly their bias and variance, with the aim of choosing one or two of the estimators which ...
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作者：LLOYD, CJ
摘要：This paper presents a new method of testing capture homogeneity in recapture experiments where there is time homogeneity. The basic set of statistics used is a lower triangular matrix whose (i, k)th element is the proportion of those animals caught on the next (i + 1)st occasion who have been caught k times until now. Both theoretical and simulation evidence is presented that the new procedure is superior to methods previously suggested.
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作者：GEORGE, EI; ROBERT, CP
作者单位：Sorbonne Universite
摘要：Capture-recapture models are widely used in the estimation of population sizes. Based on data augmentation considerations, we show how Gibbs sampling can be applied to calculate Bayes estimates in this setting. As a result, formulations which were previously avoided because of analytical and numerical intractability can now be easily considered for practical application. We illustrate this potential by using Gibbs sampling to calculate Bayes estimates for a hierarchical capture-recapture model...
