A New Generalized Heterogeneous Data Model (GHDM) to Jointly Model Mixed Types of Dependent Variables

• Activity Number: 621
• Type: Invited
• Date/Time: Thursday, August 13, 2015 : 8:30 AM to 10:20 AM
• Sponsor: Transportation Statistics Interest Group
• Author(s): Chandra R. Bhat*
• Companies: The University of Texas at Austin
• Keywords: Latent factors ; big data analytics ; high dimensional data ; MACML estimation approach ; mixed dependent variables ; structural equations models

Abstract

This paper formulates a generalized heterogeneous data model (GHDM) that jointly handles mixed types of dependent variables¬including multiple nominal outcomes, multiple ordinal variables, and multiple count variables, as well as multiple continuous variables¬by representing the covariance relationships among them through a reduced number of latent factors. Sufficiency conditions for identification of the GHDM parameters are presented. The maximum approximate composite marginal likelihood (MACML) method is proposed to estimate this jointly mixed model system. This estimation method provides computational time advantages since the dimensionality of integration in the likelihood function is independent of the number of latent factors. The study undertakes a simulation experiment within the virtual context of integrating residential location choice and travel behavior to evaluate the ability of the MACML approach to recover parameters. The simulation results show that the MACML approach effectively recovers underlying parameters, and also that ignoring the multi-dimensional nature of the relationship among mixed types of dependent variables can lead not only to inconsistent parameter