What is it?
A global minimum is the lowest value of anywhere; a local minimum is lowest only in a neighbourhood. In optimization the difference between the two is the difference between a good model and a stuck one.
Formulas
- is a global minimum
- is a local minimum
Where it shows up in computing
Cost minimization and profit maximization are the native language of operations research.
Where it shows up in AI
Training is the search for parameters that minimize the loss — in practice, a good local minimum.
Where is it used?
Computing topics reachable from here, through the chain of ideas that leads to them:
What depends on it
This page has the essentials. A fuller treatment (intuition, formal definition, worked example) is on the way.