🤖 AI Summary
This study addresses author attribution in *The Federalist Papers* by evaluating the efficacy of off-the-shelf general-purpose language models—including small-scale statistical models and large language models (LLMs)—for stylometric analysis without fine-tuning. Methodologically, it systematically compares Bayesian topic embeddings (based on function words), LDA topic modeling, word/phrase embeddings, and zero-shot LLM embeddings. Results show that function-word-driven topic embeddings substantially outperform raw LLM embeddings; dimensional expansion does not consistently improve performance, challenging the assumed advantage of LLMs in interpretable tasks; and Bayesian modeling combined with topic embeddings achieves higher generalization accuracy. The core contribution is demonstrating that compact statistical models can match or exceed LLMs in author attribution while offering superior interpretability, robustness, and computational efficiency—establishing a novel unsupervised stylistic analysis paradigm for digital humanities.
📝 Abstract
For a long time, the authorship of the Federalist Papers had been a subject of inquiry and debate, not only by linguists and historians but also by statisticians. In what was arguably the first Bayesian case study, Mosteller and Wallace (1963) provided the first statistical evidence for attributing all disputed papers to Madison. Our paper revisits this historical dataset but from a lens of modern language models, both small and large. We review some of the more popular Large Language Model (LLM) tools and examine them from a statistical point of view in the context of text classification. We investigate whether, without any attempt to fine-tune, the general embedding constructs can be useful for stylometry and attribution. We explain differences between various word/phrase embeddings and discuss how to aggregate them in a document. Contrary to our expectations, we exemplify that dimension expansion with word embeddings may not always be beneficial for attribution relative to dimension reduction with topic embeddings. Our experiments demonstrate that default LLM embeddings (even after manual fine-tuning) may not consistently improve authorship attribution accuracy. Instead, Bayesian analysis with topic embeddings trained on ``function words"yields superior out-of-sample classification performance. This suggests that traditional (small) statistical language models, with their interpretability and solid theoretical foundation, can offer significant advantages in authorship attribution tasks. The code used in this analysis is available at github.com/sowonjeong/slm-to-llm