"A variable that gives the appropriate label of an observation after allocation to one of several possible categories, for example, marital status: married, single or divorce, or blood group: A, B, AB or O. The categories are often given numerical labels but for this type of data these have no numerical significance."
Also known as
- Discrete variable (although this can also refer to an integer variable)
- Qualitative variable
- Nominal variable
- B. S. Everitt (2002): The Cambridge Dictionary of Statistics, Second Edition, Cambridge.