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Clustering bivariate mixed-type data via the cluster-weighted model

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The cluster-weighted model (CWM) is a mixture model with random covariates that allows for flexible clustering/classification and distribution estimation of a random vector composed of a response variable and a set of covariates. Within this class of models, the generalized linear exponential CWM is here introduced especially for modeling bivariate data of mixed-type. Its natural counterpart in the family of latent class models is also defined. Maximum likelihood parameter estimates are derived using the expectation-maximization algorithm and some computational issues are detailed. Through Monte Carlo experiments, the classification performance of the proposed model is compared with other mixture-based approaches, consistency of the estimators of the regression coefficients is evaluated, and several likelihood-based information criteria are compared for selecting the number of mixture components. An application to real data is also finally considered.

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The authors acknowledge the financial support from the Grant “Finite mixture and latent variable models for causal inference and analysis of socio-economic data” (FIRB 2012-Futuro in ricerca) funded by the Italian Government (RBFR12SHVV).

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Correspondence to Antonio Punzo.

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Punzo, A., Ingrassia, S. Clustering bivariate mixed-type data via the cluster-weighted model. Comput Stat 31, 989–1013 (2016). https://doi.org/10.1007/s00180-015-0600-z

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  • Mixture models with random covariates
  • Model-based clustering
  • Cluster-weighted models
  • Generalized linear models
  • Mixed-type data