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Machine Learning

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K-means clustering, finding groups nobody labeled
PCA, squashing many features into a few that matter
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Machine Learning

Math Foundations4

Supervised Learning6

Training & Evaluation4

Unsupervised Learning & Ensembles3

K-means clustering, finding groups nobody labeled
PCA, squashing many features into a few that matter
Ensembles, random forests, and boosting

Neural Networks4

Tools & Practice6

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PCA, squashing many features into a few that matter

How principal component analysis finds the handful of directions in your data that carry almost all the real information, and drops the rest.

9 min readUpdated 2026-09-03machine-learningunsupervised-learningpcadimensionality-reduction