Ranking blocks
Default algorithmic signals
In addition to manual or variable-based blocks, AB Tasty Recommendations & Merchandising provides default algorithmic logic for several ranking blocks, for example Associated Products and Similar Products.
These are powered by three main signals:
Co-occurrence
TF-IDF
Semantic
Co-occurrence
Definition: Co-occurrence measures how often two products appear together in the same context (same basket, same purchase, or same browsing session).
Logic: The more frequently two products are seen or bought together, the stronger their association score.
Example use cases:
Associated products (“Frequently bought together”): Phone + Protective Case
Complementary products: Printer + Ink Cartridges
TF-IDF (Term Frequency – Inverse Document Frequency)
Definition: A weighting method that adjusts the co-occurrence score to reduce the bias of overly generic products.
Why it matters: Popular products (gift cards, batteries, etc.) tend to appear in many baskets and could dominate co-occurrence. TF-IDF down-weights such generic items and highlights more relevant, less obvious associations.
Example use cases:
Associated products with relevance: Instead of recommending a gift card with every book, TF-IDF will surface the next tome in the same series.
Similar products: Boosts underexposed or niche products, giving visibility to new arrivals or long-tail items.
Semantic (on demand)
Definition: Semantic similarity measures how closely products relate to each other based on their descriptions, attributes, and catalog metadata, rather than just co-viewing or co-purchasing patterns.
Logic: By analyzing product text and attributes, semantic algorithms identify products that “feel alike” in style, function, or category.
Example use cases:
Similar products on PDP: A customer viewing a red running shoe could be shown other running shoes of similar style or color.
Alternative discovery: Highlight stylistically close items when co-occurrence data is too sparse (e.g., for new products).
How AB Tasty uses them
Both the “Associated Products” and “Similar Products” blocks sort results using:
Co-occurrence (frequency)
TF-IDF (relevance adjustment)
Semantic similarity can be activated on demand to enrich Similar Products recommendations and improve discovery when behavioral data is limited.
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