Actually when it comes to quantitative data, there are 4 levels, but who’s counting? (Besides Goldilocks.)
- Nominal (categorical) data are names or categories: (gender, religious affiliation, days of the week, yes or no, and so on)
- Ordinal data are like the pain scale. Each number is higher (or lower) than the next but the distances between numbers are not equal. In others words 4 is not necessarily twice as much as 2; and 5 is not half of 10.
- Interval data are like degrees on a thermometer. Equal distance between them, but no actual “0”. 0 degrees is just really, really cold.
- Ratio data are those with real 0 and equal intervals (e.g., weight, annual salary, mg.)
(Of course if you want to collect QUALitative word data, that’s closest to categorical/nominal, but you don’t count ANYTHING. More on that another time.)
CRITICAL THINKING: Where are the levels in Goldilocks and the 3 levels of data at this link: https://son.rochester.edu/research/research-fables/goldilocks.html ?? Would you measure soup, bed, chairs, bears, or other things differently? Why was the baby bear screaming in fright?