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#machine-learning
2 articles
01
2026-08-27
·
Machine Learning Basics
·
★ MEMBER
·
10 min read
Imbalanced Data in Practice — What to Optimize When 99% Is Normal
When only 1% of your data is positive, accuracy lies. We build up from the confusion matrix to PR curves, class weighting, resampling, probability calibration, and deriving the decision threshold from cost — no prior knowledge assumed.
02
2026-08-04
·
Machine Learning Basics
·
FREE
·
6 min read
What Machine Learning Really Is — Understanding “Learning” Without the Math
What actually separates writing a program from training a model. Rules versus examples, memorization versus generalization, and a map of supervised, unsupervised, and reinforcement learning — with almost no math.