Item Coverage#
The share of items that the system is able to recommend.
Important
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What it is#
Item coverage is the fraction of individual items the recommender is able to recommend at all — for which it can produce a prediction or place in a list. It asks how many products can the system reach?, item by item:
What limits it#
Items with no or few interactions — new or niche products (the cold-start problem, data sparsity) — may be impossible to recommend, dragging item coverage down. Content-based signals or hybrid models raise it by letting the system reason about unseen items from their features.
Recommendability#
Item coverage is about recommendability (can this item ever surface?), whereas catalog coverage is about how much of the catalog actually surfaces in practice.
Theme: Recommender Systems · All terminology
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Mind map — connected ideas
Catalog Coverage · User Coverage · Long-Tail Items · Relevance in Recommender Systems · Intra-List Diversity (ILD) · Diminishing Utility
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More in Recommender Systems
Catalog Coverage · Cosine Similarity of Item Features · Diminishing Utility · Diversity (in Recommender Systems) · Dominating in Recommender Systems · Genre Overlap · Hit Rate (HR) · Intra-List Diversity (ILD) · Jaccard index · Novelty (in Recommender Systems) · Relevance in Recommender Systems · Self-Information of Popularity · User Coverage
See also
Source article Adapted (context, re-expressed) in our own words from: Item Coverage (insightful-data-lab.com).