A numeric - multi is a variable set consisting of related numeric variables. Such data arise in lots of contexts, such as:
- From questions in surveys. For example:
Next to the brands below, please indicate how
many times you have purchased them in the past week.
- Database (e.g., purchases for different categories of product, where each product is represented by a different variable).
- Geography (e.g., longitude, latitude).
- Biology (e.g., measurements of different aspects of a leaf).