This encyclopaedia entry introduces readers to quantitative research methods involved in investigations of data-driven learning (DDL). The piece opens by briefly defining two key terms, DDL and quantitative research methods, in addition to the underlying assumptions of quantitative approaches more broadly. Then, readers are introduced to common quantitative designs and samples that have been used in prior DDL research. Next, the piece transitions to highlighting some of the most common targets of inquiry in quantitative DDL designs. Typically, this has consisted of L2 linguistic foci involving writing skills, vocabulary, and lexico-grammar, among others. Finally, the piece closes with a discussion of frequently used instruments such as surveys, tests, student-produced essays, and tracking data, which have been analyzed using both descriptive and inferential statistics.