Four Million Photographs and Nobody to Look at Them: Self-Supervised, Semi-Supervised and Contrastive Learning

Deep End Era. Engineering with Sankalp · Oct 28, 2026 · 52m

A fictional Scottish conservation trust has four million camera-trap photos, eleven thousand labels and just forty-one tagged wildcats. Engineer Kofi Mensah tells ecologist Mairi Campbell that the unlabelled photos are her biggest asset. Part eighteen of The Deep End's Machine Learning series explains how models learn to see without labels, from BERT and SimCLR to CLIP, FixMatch and Snorkel, and where the assumptions behind them break. Cross-references: ep15, ep96, ep101, parts 1, 2, 9, 14, 17, 19, 20. Kestrel Hills Trust, Mairi and Kofi are fictional.

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