Two spam filters scored over 97% accuracy. One missed 21% of spam. Why accuracy fails on imbalanced data, and what recall and F1 reveal instead.
Tag: logistic regression
Linear Algebra Behind for Cybersecurity ML Models
Naive Bayes assumes every feature is independent. For spam detection, that’s provably false — words in a sentence are obviously correlated. The model works well anyway. Figuring out why a wrong assumption still produces a right answer taught me more than a correct model would have. It’s also the thing that shifted how I read…