AI engineering glossary · Feature engineering data prep
What is frequency encoding?
Frequency encoding (also called Count encoding): Replacing each category with how often it appears in the training data, either as a count or a proportion. It needs no target, gives one numeric column and can help when frequency itself is informative, but different categories with equal counts become indistinguishable.
Frequency encoding: an example
If Bengaluru appears in 2,000 of 10,000 orders, it is encoded as 2,000 (or 0.2).
Related terms
More Feature engineering data prep terms
- Geospatial features
- Group-aware splitting
- Hashing trick
- Hashing vectorizer
- Haversine distance
- High-cardinality feature
- Hot-deck imputation
- Information value
Where you learn it
Frequency encoding is part of the AI Engineering Program, which teaches it with notes, a hands-on lab and an exam. The first lesson is free.