Title: Multivariate conditional transformation models
Authors: Thomas Kneib - University of Goettingen (Germany) [presenting]
Nadja Klein - Humboldt University Berlin (Germany)
Torsten Hothorn - University of Zurich (Switzerland)
Abstract: Regression models describing the joint distribution of multivariate response variables conditional on covariate information have become an important aspect of contemporary regression analysis. However, a limitation of such models is that they often rely on rather simplistic assumptions, e.g. a constant dependency structure that is not allowed to vary with the covariates. We propose a general framework for multivariate conditional transformation models that overcomes such limitations and describes the full joint distribution in simple, interpretable terms. Among the particular merits of the framework are that it can be embedded into likelihood-based inference and allows the dependence structure to vary with the covariates. In addition, the framework scales beyond bivariate response situations, which were the main focus of earlier investigations. We illustrate the application of multivariate conditional transformation models in a trivariate analysis of childhood undernutrition and demonstrate empirically that even complex multivariate data-generating processes can be inferred from observations.