A Stylometric Analysis of Seneca's disputed plays. Authorship Verification of <em>Octavia</em> and <em>Hercules Oetaeus</em>

Seneca's authorship of Octavia and Hercules Oetaeus is disputed. This study employs established computational stylometry methods based on character n-gram frequencies to investigate this case. Based on a Principal Component Analysis (PCA) of stylistic similarities within the Senecan corpus, Octavia and Phoenissae emerge as outliers, while Hercules Oetaeus only stands out when the text is split in half. Subsequently, applying PCA and Bootstrap Consensus Trees (BCT) to a corpus of distractor texts, both disputed plays align with the Senecan cluster/branch. The General Impostors method confidently reports Seneca as the author of the disputed plays under various scenarios. However, upon closer examination of text segments, indications of mixed authorship arise. Based on computational stylometry, it appears that the disputed were in large part, but not wholly, written by Seneca.