# Restart hill climbing

Last edited: 2024-02-24

# Random restart hill climbing

Suppose we have a optimisation problem where $A$ has some sense of neighbourhood $N(a)$ for each point $a \in A$.

Then we want to run Hill climbing but try to get around the issue with only finding local optimum by at the end of a run restarting in a new place.

There are lots of choices and optimisations to make here, we will need to decide a stopping condition.

  • Number of iterations.
  • Stop improving on the optimum value.
  • A % of coverage of the points.

We can also make optimisations like remembering where a point lead us and choosing not to revisit the point - Memoization .

# Run time

The run time can vary, however if we use Memoization we will try to save on number of times we run the function we are trying to optimise.

# Correctness

This has a higher chance of finding a global optimum but no guarantee.