Sigmoid Derivative

Domain: Math & Logic for AI

🎯 Motivation

The slope of sigmoid, used in backpropagation. Maxes at 0.25, which causes vanishing gradients in deep networks.

📋 Concrete Example

Sigmoid derivative at x=0 is 0.25 (steepest). At extremes it approaches 0, meaning gradients vanish.

🔗 Analogy

Like a hill that is flattest at the top and bottom - hard to slide down when there is no slope.