Posts tagged linear model
Heteroscedastic Bayesian Robust Regression
- 30 April 2026
The PyMC gallery has two robust regression notebooks: one with a Student-t likelihood (pymc-examples:GLM-robust) and one with the Hogg (2010) signal-vs-noise mixture (pymc-examples:GLM-robust-with-outlier-detection). Both protect against vertical outliers (points with unusual response values), but neither defends against leverage points: observations far from the bulk of the predictor space, which can drag the regression line even under a heavy-tailed likelihood.
Simpson’s paradox
- 12 September 2024
Simpson’s Paradox describes a situation where there might be a negative relationship between two variables within a group, but when data from multiple groups are combined, that relationship may disappear or even reverse sign. The gif below (from the Simpson’s Paradox Wikipedia page) demonstrates this very nicely.
Multivariate Gaussian Random Walk
- 02 February 2023
This notebook shows how to fit a correlated time series using multivariate Gaussian random walks (GRWs). In particular, we perform a Bayesian regression of the time series data against a model dependent on GRWs.
GLM: Robust Linear Regression
- 10 January 2023
Duplicate implicit target name: “glm: robust linear regression”.