poptally

confirmedupstream bugPython · RecBole / PyTorchSystems & data structuresJuly 25, 2026

the question

Does RecBole's Pop baseline accumulate item popularity correctly across duplicate indices within a batch?

what came out

RecBole's Pop counts with advanced-index assignment item_cnt[item]=item_cnt[item]+1, which does not accumulate duplicate indices, so a 300x intra-batch item is counted once. It becomes a per-batch document frequency and inverts the popularity ranking; index_add_ fixes it. Open issue #2198.

method & receipts

Result: confirmed
Reproducible — one script re-runs the whole thing from scratch.
Tested — a correctness/benchmark suite ships alongside the code.

→ read the code and re-run it

github.com/v-code01/poptally