# What is the difference between ordinal regression and ranking?

In both ordinal regression and ranking you are learning from an ordered dependent variables, so my question is:

What is the difference in formulation (if any) between the ordinal regression problem and a learning to rank problem?

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"Ranking" per Everitt (at least, an earlier edition) just means " the process of sorting a set of variables into ascending or descending order". So, what do you mean by ranking? –  Peter Flom Oct 28 '12 at 17:24
I mean ranking in the context of machine learning: en.wikipedia.org/wiki/Learning_to_rank –  Fabian Pedregosa Oct 28 '12 at 17:36