Implementation of RecSys Metrics

[kamalojasv181]

🚀 Feature

To add some more metrics used in Recommendation Systems with tests that can directly be used. Here is the list (@alykhantejani @vfdev-5 feel free to add more):

• NDCG

[kanpuriyanawab]

Can I contribute to this one ?

[vfdev-5]

@shivance yes, sure. Do you have a recsys metric in mind to implement ?

[kanpuriyanawab]

FactorizedTopK could be a place to start? I've also seen some systems implement Mean Average Precision MAP

I'm not aware of many metrics specific to recsys, so am open to learn !

[vfdev-5]

@shivance how about implementing hitrate, mean reciprocal rank etc ?
Some refs to check:

• https://github.com/catalyst-team/catalyst/blob/master/catalyst/metrics/functional/_hitrate.py
• https://github.com/catalyst-team/catalyst/blob/master/catalyst/metrics/functional/_mrr.py
• https://github.com/zuoxingdong/recsys_metrics/tree/master/recsys_metrics