I have a list of items, each associated with their optimal ranking in the list. How can I give a score to a given order of the list.
For instance, if I know that the optimal ranking is: 4 3 5 1 2 And the current ranking of my items is 1 2 3 4 5,
Which metric can I use as a fitness metric (or score) in order to give my algorithm an information as to whether the current ranking configuration is close to the optimal ranking or not?
I don't think I can use Discounted Cumulative Gain (DCG) as all of my items are equally important (it's not more important to rank one of the items well rather than another)