[Statlist] Research Seminar in Statistics | *FRIDAY 19 APRIL 2024* | GSEM, University of Geneva

[gsem-support-instituts]

Dear all,

We are pleased to invite you to our next Research Seminar, organized by Professor Sebastian Engelke on behalf of the Research Center for Statistics
< https://www.unige.ch/gsem/en/research/institutes/rcs/team/ >.

FRIDAY 19 APRIL 2024, at 11:15 am, Uni Mail M 4220.

Bi-factor and second-order copula models for item response data
Aristidis K. NIKOLOULOPOULOS, University of East Anglia, UK
< https://research-portal.uea.ac.uk/en/persons/aristidis-k-nikoloulopoulos >

ABSTRACT:
Bi-factor and second-order models based on copulas are proposed for item response data, where the items are sampled from identified subdomains of some larger domain such that there is a homogeneous dependence within each domain. Our general models include the Gaussian bi-factor and second-order models as special cases and can lead to more probability in the joint upper or lower tail compared with the Gaussian bi-factor and second-order models. Details on maximum likelihood estimation of parameters for the bi-factor and second-order copula models are given, as well as model selection and goodness-of-fit techniques. Our general methodology is demonstrated with an extensive simulation study and illustrated for the Toronto Alexithymia Scale. Our studies suggest that there can be a substantial improvement over the Gaussian bi-factor and second-order models both conceptually, as the items can have interpretations of discretized maxima/minima or mixtures of discretized means in comparison with discretized means, and in fit to data.

> View the Research Seminar agenda: < https://www.unige.ch/gsem/en/research/seminars/rcs/ >

Regards,


Marie-Madeleine

Marie-Madeleine Novo
Assistant to the Research Institutes
gsem-support-instituts at unige.ch