Talk:Tournament selection

Latest comment: 10 years ago by 138.100.74.81 in topic Mathematically wrong

The pseudo code edit

The pseudo code seems wrong. It should be:

choose k (the tournament size) individuals from the population at random
select the best of the k individuals

The statement "The chosen individual can be removed from the population that the selection is made from if desired, otherwise individuals can be selected more than once for the next generation" is wrong. For a population of size n, there are n tournaments. If the selected individual is removed from the population, then by the time the nth tournament has been run, there will be n - n individuals who have not been selected. At that point there is no actual selection happening. —Preceding unsigned comment added by 129.15.40.22 (talk) 21:50, 21 June 2010 (UTC)Reply

The cited paper does not seem to use the p parameter. Can someone add a references to a paper that introduces this parameter? If not, it probably should not be in wikipedia. —Preceding unsigned comment added by Mlittman (talkcontribs) 19:44, 24 October 2010 (UTC)Reply

Mathematically wrong edit

If you do the mathematics you will find that either k has to be 0 or that p has to be 1. This doesn't seem right.

--Astenorh (talk) 13:36, 2 May 2011 (UTC)Reply

Right, there's a (1-p)^k probability that none of the k participants is selected. This could be solved by saying that the worst individual is always selected with a probability of (1-p)^(k-1), or dividing all the probabilities by 1-(1-p)^k. In any case, a clarification is needed. 138.100.74.81 (talk) 08:27, 3 June 2013 (UTC)Reply