BEGIN:VCALENDAR VERSION:2.0 PRODID:-//132.216.98.100//NONSGML kigkonsult.se iCalcreator 2.20.4// BEGIN:VEVENT UID:20260621T060446EDT-2173SEC9tu@132.216.98.100 DTSTAMP:20260621T100446Z DESCRIPTION:Singularities of the information matrix and longitudinal data w ith change points\n\n\n Abstract:\n\n\nNon-singularity of the information m atrix plays a key role in model identification and the asymptotic theory o f statistics. For many statistical models\, however\, this condition seems virtually impossible to verify. An example of such models is a class of m ixture models associated with multi-path change-point problems (MCP) which can model longitudinal data with change points. The MCP models are simila r in nature to mixture-of-experts models in machine learning. The question then arises as to how often the non-singularity assumption of the informa tion matrix fails to hold. We show that\n\nthe set of singularities of the information matrix is a nowhere dense set\, i.e. geometrically negligible \, if the model is identifiable and some mild smoothness conditions hold. Under further smoothness conditions we show that the set is also of measur e zero\, i.e. both geometrically and analytically negligible. In view of t hese results\, we further study class of semiparametric MCP models\, thus paving the way for establishing asymptotic normality of the maximum likeli hood estimates (MLE) and statistical inference of the unknown parameters i n such models.\n\n\n Speaker\n\n\nMasoud Asgharian is a Professor in the De partment of Mathematics and Statistics at 91ºÚÁÏÍø. His research interest is on survival analysis\, change-point problems\, causal inferenc e\, and variable selection.\n DTSTART:20190118T203000Z DTEND:20190118T213000Z LOCATION:Room 1205\, Burnside Hall\, CA\, QC\, Montreal\, H3A 0B9\, 805 rue Sherbrooke Ouest SUMMARY:Masoud Asgharian (91ºÚÁÏÍø) URL:/mathstat/channels/event/masoud-asgharian-mcgill-u niversity-293312 END:VEVENT END:VCALENDAR