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seminars:datasci:200326 [2020/03/20 17:41] – created qyuseminars:datasci:200326 [2020/03/20 17:43] (current) qyu
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 +<WRAP centeralign>##Data Science Seminar##\\ Hosted by Department of Mathematical Sciences</WRAP>
 +
 +  * Date: Tuesday, March 26, 2020
 +  * Time: 12:00pm -- 1:00pm
 +  * Room: WH-100E
 +  * Speaker: Wangshu Tu (Binghamton University)
 +  * Title: A family of mixture models for biclustering
 +
 +<WRAP center box 80%>
 +<WRAP centeralign>**//Abstract//**</WRAP>
 +Biclustering allows for simultaneous clustering of the observations and
 +variables. Martella et. al (2008) introduced biclustering in a model-based
 +clustering framework by utilizing a structure similar to a mixture of
 +factor analyzer structures such that observed variables are modelled using
 +a latent variable that is assumed to be from a MVN(0, I). In Martella et.
 +al (2008), clustering of variables was introduced by imposing constraints
 +on the entries of the factor loading matrix to be 0 and 1. However, this
 +approach restricts the non-zero off-diagonal entries of the covariance
 +matrix to be 1, which is very restrictive. Here, we assume the latent
 +variable to be from a MVN(0,T) where T is a diagonal matrix and hence, the
 +non-zero off-diagonal entires of the covariance matrix are not restricted
 +to be equal to 1. A family of models are developed by imposing constraints
 +on the components of the covariance matrix. An alternating expectation
 +conditional maximization(AECM) algorithm is used for parameter estimation.
 +Proposed method will be illustrated using simulated and real datasets. The
 +presentation will conclude with some on-going work and future research
 +directions.
 +
 +</WRAP>