Having little experience in ML: Write the sets in ascending order and, treating them as an n+1 dimensional vector, and use Euclidean distance. Googling, you c

Having little experience in ML: Write the sets in ascending order and, treating them as an n+1 dimensional vector, and use Euclidean distance. Googling, you could look at section 2.1 of https://papers.nips.cc/paper/3708-ranking-measures-and-loss-functions-in-learning-to-rank.pdf https://papers.nips.cc/paper/3708-ranking-measures-and-loss-...