Prof. Alan Agresti on modelling ordinal data, issues with Wald based inferences, and GEE for ordinal data

Yesterday we were very pleased to welcome Prof. Alan Agresti, from the University of Florida, to give a departmental seminar at the London School of Hygiene & Tropical Medicine. Prof. Agresti gave a very interesting seminar, covering a wide range of topics, which came out of writing his most recent book – ’Foundations of Linear and Generalized Linear Models’. Among these was some of the problems that can arise when ordinal outcomes are modelled using linear regression models. He then discussed a proposal for a new way of representing covariate effects in ordinal regression models, in a so called superiority measure. Next he discussed some of the problems that can arise with Wald based inferences, a topic I’ve touched upon before here. Prof. Agresti then discussed some issues with residuals in GLMs, and some recently new methods for modelling multivariate using generalized estimating equations.

An audio/slide recording of Prof. Agresti’s seminar is available here.

A statistician’s initial experiences of Git/GitHub

A friend of mine has been telling me for some time that I should try using Git / GitHub to keep track of my files. In this post I’ll give a bit of an overview of these (or at least my understanding of them so far!), and some of my experiences of using them so far. Some of the terminology is (in my experience) a bit confusing, so I’ll attempt to give an intuitive introduction. For any Git experts out there, please put me straight (in a comment) if I’ve got something wrong!

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