Which type of data is represented by numerical values on at least an ordinal level?

Quantitative data is characterized by its representation of numerical values that can be measured and analyzed statistically. This type of data allows for a range of mathematical operations, such as calculating averages, variances, and standard deviations, particularly because it is associated with numerical values that can be classified on an ordinal level or higher. Ordinal data represents categories with a rank order; for instance, a survey rating system from 1 to 5 can be classified as ordinal due to the inherent ordering of the responses.

In contrast, qualitative data refers to non-numerical information, often descriptive in nature, which typically cannot be subjected to mathematical operations in the same way as quantitative data. The terms primary and secondary data relate instead to the source and collection method of the information rather than the nature of the data itself, making them less relevant when determining which type of data involves numerical values.