Textbooks Are All You Need II: phi-1.5 technical report

TL;DR

This paper introduces phi-1.5, a 1.3 billion parameter Transformer model trained exclusively on textbook-like data, achieving performance comparable to larger models and demonstrating capabilities in reasoning, coding, and mathematics.

Contribution

The paper presents phi-1.5, a novel smaller language model trained on textbook data, showing competitive performance and insights into model traits and biases without web data.

Findings

phi-1.5 performs on par with larger models on natural language tasks

It surpasses many non-frontier LLMs in reasoning and coding tasks

The model exhibits both strengths and weaknesses similar to larger models

Abstract

We continue the investigation into the power of smaller Transformer-based language models as initiated by \textbf{TinyStories} -- a 10 million parameter model that can produce coherent English -- and the follow-up work on \textbf{phi-1}, a 1.3 billion parameter model with Python coding performance close to the state-of-the-art. The latter work proposed to use existing Large Language Models (LLMs) to generate ``textbook quality" data as a way to enhance the learning process compared to traditional web data. We follow the ``Textbooks Are All You Need" approach, focusing this time on common sense reasoning in natural language, and create a new 1.3 billion parameter model named \textbf{phi-1.5}, with performance on natural language tasks comparable to models 5x larger, and surpassing most non-frontier LLMs on more complex reasoning tasks such as grade-school mathematics and basic coding. More generally, \textbf{phi-1.5} exhibits many of the traits of much larger LLMs, both good -- such as the ability to ``think step by step" or perform some rudimentary in-context learning -- and bad, including hallucinations and the potential for toxic and biased generations -- encouragingly though, we are seeing improvement on that front thanks to the absence of web data. We open-source \textbf{phi-1.5} to promote further research on these urgent topics.