2019/04/16
Modeling Short Time Series with Prior Knowledge
I just published a longer case study, Modeling Short Time Series with Prior Knowledge: What ‘Including Prior Information’ really looks like. It is generally difficult to model time series when there is insuffient data to model a (suspected) long seasonality. We show how this difficulty can be overcome by learning a seasonality on a different, long related time series and transferring the posterior as a prior distribution to the model of the short time series.
2019/03/23
The Probabilistic Programming Workflow
Last week, I gave a presentation about the concept of and intuition behind probabilistic programming and model-based machine learning in front of a general audience. You can read my extended notes here. Drawing on ideas from Winn and Bishop’s “Model-Based Machine Learning” and van de Meent et al.’s “An Introduction to Probabilistic Programming”, I try to show why the combination of a data-generating process with an abstracted inference is a powerful concept by walking through the example of a simple survival model.
2019/02/24
Problem Representations and Model-Based Machine Learning
Back in 2003, Paul Graham, of Viaweb and Y Combinator fame, published an article entitled “Better Bayesian Filtering”. I was scrolling chronologically through his essays archive the other day when this article stuck out to me (well, the “Bayesian” keyword). After reading the first few paragraphs, I was a little disappointed to realize the topic was Naive Bayes rather than Bayesian methods. But it turned out to be a tale of implementing a machine learning solution for a real world application before anyone dared to mention AI in the same sentence.