He is interested in European literature of the Renaissance and the Baroque, classical heritage in early modern literature, and scholarly editing (his most recent book is a critical edition of 16th-century Polish translations of Dialogue of Salomon and Marcolf). For a couple of years, Eder has been focusing on digital methods applied to literary and linguistic studies, with special attention paid to computer-based stylometry and non-traditional authorship attribution. His work is now focused on a thorough re-examination of current attribution methods and applying them to non-English languages, e.g. Latin and Ancient Greek.