Standard Deviation
Domain: Math & Logic for AI
🎯 Motivation
The square root of variance, in the same units as the data. Easier to interpret.
📋 Concrete Example
If variance is 25, standard deviation is 5. Most data falls within 2 standard deviations of the mean.
🔗 Analogy
Like a margin of error - plus or minus 5 marks tells you how spread out exam scores typically are.