In this video I describe how psychologists and social scientists often treat ordinal data as if it were interval data, which is a cause of some debate between pure statisticians and more pragmatic researchers. I discuss why this may or may not be appropriate in varying situations, and consider the possible justifications for taking this approach.

Stevens, S.S. (1946) On the Theory of Scales of Measurement, Science, New Series, Vol. 103, No. 2684 (Jun. 7, 1946), pp. 677-680
https://www.fpce.uc.pt/niips/novoplano/mip1/mip1_201314/scales/Stevens_1946.pdf

Simon Kemp, Randolph C. Grace, Using ordinal scales in psychology, Methods in Psychology, Volume 5, 2021,100054, ISSN 2590-2601,
https://doi.org/10.1016/j.metip.2021.100054.
(https://www.sciencedirect.com/science/article/pii/S2590260121000114)