Seminar in applied mathematics and statistics
SPEAKER: Jose M. Pena (STIMA, IDA, LiU).
TITLE: Unifying Gaussian LWF and AMP Chain Graphs to Model Interference
ABSTRACT: An intervention may have an effect on units other than those to which it was administered. This phenomenon is called interference and it usually goes unmodeled. In this seminar, we will propose to combine Lauritzen-Wermuth-Frydenberg and Andersson-Madigan-Perlman chain graphs to create a new class of causal models that can represent interference relationships. Specifically, we will define the new class of models, and introduce global and local and pairwise Markov properties for them. We will also propose an algorithm for maximum likelihood parameter estimation for the new models, and report experimental results. We will also argue that the new models model interference by so-called contagion which, intuitively, means that one individual's treatment does not affect another individual's outcome directly but via the first individual's outcome. Finally, we will adapt Pearl's do-calculus for causal effect identification on the new models.
Tea and chocolate will be served in room 04.4.19 after the seminar.
Friday, February 8, 2019, at 14.15: Massimiliano Tamborrino
Friday, February 15, 2019 at 14.15: Irene Tubikanec