Kendall-Tau correlation

jma127 / pyltr

Python learning to rank (LTR) toolkit

BSD 3-Clause "New" or "Revised" License

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Kendall-Tau correlation #5

Open chrisplyn opened 7 years ago

chrisplyn commented 7 years ago

Hi Jerry, Are you planning to implement the calc_swap_deltas method for KT metrics? As I remember there is a build-in function in scipy to calculate KT. Thanks

jma127 commented 7 years ago

Hi Chris, the scipy function for KT won't really help for calc_swap_deltas since we'd still have to run it O(n^2) times for a total runtime of O(n^4). However, there is a fairly straightforward O(n^2) algorithm for calculating the swap deltas -- will leave this issue open in case anyone wants to tackle it.