WHAT IT IS
Phi is a family of small language models introduced by Microsoft Research in June 2023. Its emphasis is data quality rather than model size: training on filtered “textbook-quality” text lets a few-billion-parameter model approach much larger ones on reasoning and coding. Phi-3 offers 3.8B, 7B and 14B sizes, and the smallest, Phi-3-mini, can run on-device. The models are released as open weights and are often used to probe the capability limits of small models.
Why it matters
It showed that curating and orchestrating data can substitute for parameter count to a surprising degree: a few-billion-parameter model trained on selected data can approach models an order of magnitude larger on some reasoning tasks.
Key specs
- Parameters
- 3.8B / 7B / 14B (Phi-3 family)
- Training data
- Mainly filtered “textbook-quality” text
- Open weights
- Yes
- Released
- 2023-06
Capabilities
Related concepts
Pretraining & Fine-tuning
Learn language first from vast unlabelled text, then specialise with little data — the most data-efficient paradigm in modern AI
Transformer Architecture
Replacing word-by-word relay with a room where everyone speaks at once, so long-range dependencies are one hop away
Model Compression
Make a model smaller, faster and cheaper with almost no accuracy loss — but you can usually have only two of the three at once
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