A reparameterization to improve numerical optimization in multivariate REML (co)variance component estimation
نویسندگان
چکیده
منابع مشابه
REML Variance-Component Estimation
In the numerous forms of analysis of variance (ANOVA) discussed in previous chapters, variance components were estimated by equating observed mean squares to expressions describing their expected values, these being functions of the variance components. ANOVA has the nice feature that the estimators for the variance components are unbiased regardless of whether the data are normally distributed...
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Rousseeuw’s minimum covariance determinant (MCD) method is a highly robust estimator of multivariate mean and covariance. In practice, the MCD covariance estimator may be singular. However, a nonsingular covariance estimator is required to calculate the Mahalanobis distance. In order to fix this singular problem, we propose an improved version of the MCD estimator, which is a combination of the...
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1 Univ. of Ljubljana, Biotechnical Fac., Dept. of Animal Science, Groblje 3, SI-1230 Domžale, Slovenia,, Ph.D., e-mail: [email protected] 2 The same address as 1 3 Departamento de Mejora Genética, Instituto Nacional de Investigación Agraria, Carretera de La Coruña, km 7, 28040 Madrid, Spain, Ph.D. Simple reparameterization to improve convergence in linear mixed models Slow convergence...
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ژورنال
عنوان ژورنال: Genetics Selection Evolution
سال: 1994
ISSN: 1297-9686
DOI: 10.1186/1297-9686-26-6-537