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ahmedfgad / GeneticAlgorithmPython

Source code of PyGAD, a Python 3 library for building the genetic algorithm and training machine learning algorithms (Keras & PyTorch).
https://pygad.readthedocs.io
BSD 3-Clause "New" or "Revised" License
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multi objective optimization - metric of quality #252

Open MichaelRara opened 7 months ago

MichaelRara commented 7 months ago

Hi, what metric is used to decide what solution in multi objective optimization is better? How do you compare them? https://pygad.readthedocs.io/en/latest/pygad_more.html#multi-objective-optimization

ahmedfgad commented 5 months ago

Hi @MichaelRara,

For multi-objective optimization, there are 2 special parent selectors:

  1. nsga2: This selects the parents based on non-dominated sorting and crowding distance.
  2. tournament_nsga2: This selects the parents using tournament selection which uses non-dominated sorting and crowding distance to rank the solutions.

So, simply the metrics are non-dominated sorting and crowding distance.