Microsoft has published the technical report for Phi-4, a 14-billion parameter language model that prioritizes data quality through strategic use of synthetic data throughout training. Unlike previous Phi models that distilled capabilities from GPT-4, Phi-4 surpasses its teacher on STEM-focused QA tasks, demonstrating that its data-generation and post-training techniques extend beyond simple distillation.

  • The model uses a training recipe focused on high-quality synthetic data rather than just organic web content or code.
  • Phi-4 substantially outperforms GPT-4 on STEM-focused question answering capabilities.
  • It achieves strong performance relative to its size, particularly on reasoning-focused benchmarks, due to improved data, training curriculum, and post-training innovations.

The report highlights that despite minimal architectural changes from phi-3, the focus on data quality allows the model to exceed teacher capabilities in specific domains.