May 18, 2017

Randking Pointwise or Pairwise

You can do ranking in two ways.

1- Pointwise
Training:
x1     engagement prob
x2     engagement prob
...


then train a model that gives a score for each and sort by score.


2- Pairwise
x1 precedes x2           1
x1 precedes x3           1
x4 precedes x2           0

have n choose 2 training like above and give scores to test set pairs in the same way.


Or you can do learn to rank: https://en.wikipedia.org/wiki/Learning_to_rank