recommenders-team/recommenders

[ASK] Question on ndcg_at_k calculation

Open

#1,962 创建于 2023年7月24日

在 GitHub 查看
 (0 评论) (0 反应) (0 负责人)Python (2,972 fork)batch import
help wanted

仓库指标

Star
 (17,706 star)
PR 合并指标
 (平均合并 6天 16小时) (30 天内合并 10 个 PR)

描述

Description

Why are we using rank ('first) to get the order of the ideal ranking instead of rank('min') or rank('average)?

https://github.com/microsoft/recommenders/blob/main/recommenders/evaluation/python_evaluation.py#L687 line 597 df_idcg["irank"] = df_idcg.groupby(col_user, as_index=False, sort=False)[ col_rating ].rank("first", ascending=False)

In this case, if there is a tied in the rating, for example, item A, B, C, D, rating is 1, 0, 0,0. Using rank('first), irank = 1,2,3,4. But should we take the tied condition into consideration, that means the irank = 1,2,2,2?

Other Comments

贡献者指南