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I have a pretty simple question. However I have searched extensively and am unable to find the answer. Is a genetic algorithm considered to be a form of unsupervised learning? I know that the algorithms evolves independently, however the fitness of each individual in the population is regularly measured (supervised?).

The objective of my algorithm is to optimize a set of heuristic weights via a genetic algorithm.

Thank you for your help! —

Leopold Joy
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  • Better ask at stats.stackexchange.com – cyborg Dec 23 '13 at 23:04
  • "Considered" screams out that this may be opinion based. Just who do you think is doing the considering? – dmckee --- ex-moderator kitten Dec 24 '13 at 02:58
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    genetic algorithm is not "learning algoritm" at all, this is an **optimization method**, it is completely different branch od CS. GA, as **any other optimization method** can be used in supervised, unsupervised, reinformcemnt learning as well as in milions other applications. So once again - GA is **not any kind of learning**, it is **optimization method**. – lejlot Jan 11 '14 at 10:49
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    Actually its not as clear-cut. Yes GA is categorized as a optimization method (or search algorithm), **however** a search algorithm can exhibit learning behaviour if it is continuously running, adapting to the dynamic environment of which the GA is used, thus exhibiting learning behaviour. – chutsu Jan 14 '14 at 21:34

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From http://en.wikipedia.org/wiki/Unsupervised_learning

In machine learning, the problem of unsupervised learning is that of trying to find hidden structure in unlabeled data. Since the examples given to the learner are unlabeled, there is no error or reward signal to evaluate a potential solution. This distinguishes unsupervised learning from supervised learning and reinforcement learning.

From which it's pretty clear that genetic algorithms are not unsupervised as they are measured against a fitness criteria. Individual mutations may not be supervised, but the system as a whole is supervised as mutations are either removed or built upon based on the resulting fitness they give the algorithm.

From http://en.wikipedia.org/wiki/Reinforcement_learning

Reinforcement learning is an area of machine learning inspired by behaviorist psychology, concerned with how software agents ought to take actions in an environment so as to maximize some notion of cumulative reward. The problem, due to its generality, is studied in many other disciplines, such as game theory, control theory, operations research, information theory, simulation-based optimization, statistics, and genetic algorithms.

Which would sort of suggest that genetic algorithms are considered to fall under reinforcement learning.

Tim B
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  • Thanks for the reply! :) In what category would you then class genetic algorithms? Are they supervised or reinforcement? – Leopold Joy Dec 23 '13 at 22:49
  • I'd say reinforcement but honestly I'm not an expert in this field, just an interested bystander - so I'm not going to present my opinion as fact...just give you sourced quotes and let you draw your own conclusion :) – Tim B Dec 23 '13 at 22:52
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Genetic Algorithms can be used for both supervised and unsupervised learning, e.g.:

Unsupervised Genetic Algorithm Deployed for Intrusion Detection, (2008). Zorana Banković, Slobodan Bojanić, Octavio Nieto, Atta Badii.

If you have labeled training data or tagged examples, then you are using supervised training.

cyborg
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  • If you are using one to learn heuristic weights for a game-playing algorithm, would that be supervised? – Leopold Joy Dec 23 '13 at 22:55
  • Yes, it is to optimize. I have updated the question. Thank you for your help! :) – Leopold Joy Dec 23 '13 at 23:07
  • ou didn't disclose the relevant info: do you have tagged examples by which you penalize/optimize/promote? If you do, then it's supervised. – cyborg Dec 23 '13 at 23:18