why synthetic data can provide better guidance to a model:
Synthetic data as a substantial component of pretraining is becoming increasingly common, and the Phi series of models has consistently emphasized the importance of synthetic data. Rather than serving as a cheap substitute for organic data, synthetic data has several direct advantages over organic data.
Structured and Gradual Learning. In organic datasets, the relationship between tokens is often complex and indirect. Many reasoning steps may be required to connect the current token to the next, making it challenging for the model to learn effectively from next-token prediction. By contrast, each token generated by a language model is by definition predicted by the preceding tokens, making it easier for a model to follow the resulting reasoning patterns.
And this section about their approach for generating that data:
Our approach to generating synthetic data for phi-4 is guided by the following principles:
- Diversity: The data should comprehensively cover subtopics and skills within each domain. This requires curating diverse seeds from organic sources.
- Nuance and Complexity: Effective training requires nuanced, non-trivial examples that reflect the complexity and the richness of the domain. Data must go beyond basics to include edge cases and advanced examples.
- Accuracy: Code should execute correctly, proofs should be valid, and explanations should adhere to established knowledge, etc.
- Chain-of-Thought: Data should encourage systematic reasoning, teaching the model various approaches to the problems in a step-by-step manner.
