It's easy to fool yourself: Case studies on identifying bias and confounding in bio-medical datasets

Subhashini Venugopalan
Arunachalam Narayanaswamy
Anton Geraschenko
Scott Lipnick
Nina Makhortova
James Hawrot
Christine Marques
Joao Pereira
Lee Rubin
Brian Wainger,
NeurIPS LMRL workshop 2019(2019)


Confounding variables are a well known source of nuisance in biomedical studies. They present an even greater challenge when we combine them with black-box machine learning techniques that operate on raw data. This work presents two case studies. In one, we discovered biases arising from systematic errors in the data generation process. In the other, we found a spurious source of signal unrelated to the prediction task at hand. In both cases, our prediction models performed well but under careful examination hidden confounders and biases were revealed. These are cautionary tales on the limits of using machine learning techniques on raw data from scientific experiments.