Theoretical perspectives of quantitative physics education research

This paper is part of the Focused Collection on Quantitative Methods in PER: A Critical Examination.] The notion of quantitative physics education research (PER) so far has been mostly limited to the mere use of statistical methods or use of computational tools for analyzing numerical data. Little attention, in fact, has been given to the underpinnings of this research paradigm. To fill the gap, this theoretical paper addresses key and yet often tacit (or even misunderstood) principles of three commonly used quantitative genres in PER, which I, respectively, refer to as measurement (quantification of individual constructs), controlled exploration of relations (quantification of relationships between multiple constructs through controlled experiments), and data mining (quantification of new information from large datasets). For each genre, I elucidate the paradigmatic basis by focusing on its ontological assumptions (theories about the reality under quantitative investigation), epistemological commitments (views about the knowledge gained through quantitative investigation), and methodological implications for empirical investigations. Although framed in the context of physics education research, the discussions herein are applicable to other discipline-based or general education research employing quantitative methods.