Showing 1 - 7 of 7
Persistent link: https://www.econbiz.de/10009735641
A dimension reduction method for model-based clustering via a finite mixture of shifted asymmetric Laplace distributions is introduced. The approach is based on existing work within the Gaussian paradigm and relies on identification of a reduced subspace. This subspace contains linear...
Persistent link: https://www.econbiz.de/10010678721
A novel model-based classification technique is introduced based on mixtures of multivariate t-distributions. A family of four mixture models is defined by constraining, or not, the covariance matrices and the degrees of freedom to be equal across mixture components. Parameters for each of the...
Persistent link: https://www.econbiz.de/10008864127
A mixture of skew-t factor analyzers is introduced as well as a family of mixture models based thereon. The particular formulation of the skew-t distribution used arises as a special case of the generalized hyperbolic distribution. Like their Gaussian and t-distribution analogues, mixtures of...
Persistent link: https://www.econbiz.de/10010871318
Parsimonious mixtures of multivariate t-factor analyzers are used for robust clustering of high-dimensional data. Sixteen parsimonious mixtures of t-factor analyzers are utilized and the AECM algorithm is used for parameter estimation. Application to compact facial representation is illustrated.
Persistent link: https://www.econbiz.de/10010752965
Robust mixture modeling approaches using skewed distributions have recently been explored to accommodate asymmetric data. Parsimonious skew-t and skew-normal analogues of the GPCM family that employ an eigenvalue decomposition of a scale matrix are introduced. The methods are compared to...
Persistent link: https://www.econbiz.de/10010719663
A mixture of latent trait models with common slope parameters for model-based clustering of high-dimensional binary data, a data type for which few established methods exist, is proposed. Recent work on clustering of binary data, based on a d-dimensional Gaussian latent variable, is extended by...
Persistent link: https://www.econbiz.de/10011209621