Variance
Domain: Math & Logic for AI
🎯 Motivation
Measures how spread out the data is from the mean. High variance means data is scattered widely.
📋 Concrete Example
Two classes both average 70. Class A scores range 65-75 (low variance). Class B ranges 40-100 (high variance).
🔗 Analogy
Like measuring how far arrows spread from the bullseye - tight cluster is low variance, scattered is high.