AI Glossary Term

What does “Gradient Descent” mean?

Definition

An optimization method that updates parameters in the direction that reduces error.

How Gradient Descent works

Diagram for Gradient Descent, a repeating loop: Start with random weights; then Measure the loss; then Compute the gradient; then Step downhill by the learning rate; then back to the start.Start with random weightsMeasure the lossCompute the gradientStep downhill by the learningraterepeat

Example

Picture standing on a foggy hillside and taking small steps in whichever direction slopes downward most steeply. Gradient descent does this with the model's loss, adjusting weights a little each step until the loss stops dropping.

Why it matters

Gradient descent and its variants are how nearly all neural networks are trained. Step size and data handling choices affect whether training succeeds.

Common questions

What is stochastic gradient descent?

A version that estimates the gradient from a small random batch of data each step, which is faster and works well in practice.

Can it get stuck?

It can slow near flat regions or settle in a local minimum, though in large networks these are usually less troublesome than expected.

What is Adam?

A popular variant that adapts step sizes per parameter using running averages of gradients.

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