Numeric data is not always as simple as it seems. Sometimes numbers represent items rather than giving us a simple count of the value of the items.

We generally have two different subsets of numeric data: one that has a base of absolute zero, for example, numbers that have a defined point of being ‘nothing’, and one that has an arbitrary zero, for example, numbers that rely on the dataset that they are a part of (e.g. in temperature zero degrees Celsius is the same as 32 degrees Fahrenheit, which is the same as -270 degrees Kelvin).

We shall come across both of these types of data that will need to be analysed.

Arbitrary zero = ‘interval scale’ (this could be the same data expressed in different forms, such as temperature, or it could be a rating scale where we rate something on a scale from 1 to 10). Each representation of the data in a numeric format could have a different meaning depending on the type of data set.

Absolute zero = ‘ratio scale’ (this is typical when we are counting quantities of items).

Join the discussion

Can you think of other examples beside temperature and rating scales that could be considered as numeric data with an ‘arbitrary zero’?

Use the discussion section below and let us know your thoughts. Try to respond to at least one other post and once you’re happy with your contribution, click the Mark as Complete button to check the Step off, then you can move to the next step.