Prompt
My recommender is giving too many popular items
Latest observation
Sep 30, 2026
OpenAI APIWeb search: off
That usually means the model is over-indexing on global popularity and not enough on personal preference, freshness, or diversity.
A few common causes and fixes:
Common causes
- Popularity bias in training data: popular items get more clicks/purchases, so the model learns to favor them.
- Objective function rewards easy wins: ranking loss may prefer items with strong average signal.
- Insufficient personalization features: user/item interactions may not be rich enough.
- Candidate generation too narrow: the retrieval stage may already be mostly popular items.
- Feedback loops: popular items get more exposure, which makes them even more popular.
Ways to reduce it
- Downweight popularity in ranking or scoring.
- Add re-ranking constraints:
- cap the number of popular items per list
- diversify by category/brand/price
- inject novelty or freshness
- Use popularity as a feature, not a dominant signal.
- Debias training data:
- exposure-aware learning
- inverse propensity weighting
- negative sampling that isn’t dominated by popular items
- Improve personalization:
- user embeddings / sequence models
- context features
- session intent
- Broaden retrieval:
- multiple candidate sources
- semantic similarity / content-based retrieval
- Tune the evaluation metric:
- track coverage, long-tail share, novelty, and personalization metrics, not just CTR/NDCG
Practical quick fixes
If you want something fast:
- Add a popularity penalty in the final score.
- Re-rank top-k with a diversity/novelty constraint.
- Mix in a percentage of long-tail items for exploration.
- Measure exposure distribution to confirm the skew.
If you want, I can help you diagnose this more precisely if you share:
- your model type,
- training objective,
- retrieval/ranking setup,
- and a sample of the top-ranked items.