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3. Ordinal Data
About this Lecture
In this lecture, we think about ordinal data and scales, focusing in particular on: (i) a classic example of one being first, second and third place in a race, irrespective of the gap in time between any two of those finishers; (ii) the application of two ordinal scales to a dataset, demonstrating the validity but potential problems with each; (iii) the median as an appropriate measure of central tendency for ordinal data; (iv) a classic example of ordinal data collection, through reporting a wellbeing score of 1-5 in a survey.
In this course, Professor Dominic Dwyer (Cardiff University) explores measurement levels and scales. In the first lecture, we think about the origin of measurement scales in psychology, and the role of Stanley Smith Stevens in establishing the four measurement levels: nominal, ordinal, interval, and ratio. In the second lecture, we think about nominal scales and their prevalence in behavioural genetics, despite statistical limitations. In the third lecture, we think about ordinal scales and their regular use in survey data collection. Next, we think about ratio scales and the importance of zero meaning something (nothing) in these scales. In the fifth lecture, we think about interval scales and their lack of applicability to ratios of data, due to the arbitrary nature of the zero value. In the sixth and final lecture, we think about how these measurement scales can be summarised and discuss some of the challenges to Stevens’ understanding of measurement.
Professor Dominic Dwyer is the chair for the BSc and MSc exam boards in the School of Psychology at Cardiff University. Professor Dwyer teaches introductory statistics for undergraduate years one and two. Professor Dwyer’s research is primarily focused on how animals and people learn, as well as how that learning is expressed as behaviour. Some key focus areas of this research are computational modelling, neurodegenerative disorders, and the assessment of individual differences. Some of Professor Dwyer’s recent publications include 'EXPRESS: Instrumental responses and Pavlovian stimuli as temporal referents in a peak procedure' (2022) and 'Face masks have emotion-dependent dissociable effects on accuracy and confidence in identifying facial expressions of emotion' (2022).
Cite this Lecture
Dwyer, D. (2022, April 20). Statistics for Psychologists – Measurement Levels - Ordinal Data [Video]. MASSOLIT. https://www.massolit.io/courses/statistics-for-psychologists-measurement-levels/ordinal-data
Dwyer, D. "Statistics for Psychologists – Measurement Levels – Ordinal Data." MASSOLIT, uploaded by MASSOLIT, 20 Apr 2022, https://www.massolit.io/courses/statistics-for-psychologists-measurement-levels/ordinal-data