Did You Know?
Level of measurement refers to the relationship among values that are assigned to the attributes for a variable.
Nominal
The nominal level is the lowest (or least precise) level of data measurement. It classifies individuals, companies, products, brands or other entities into categories where no order is implied. It is non comparative, usually representing a description or name.
Did You Know?
Numbers or other symbols are assigned to a set of categories for the purpose of naming, labeling, or classifying the observations.
At the nominal level of measurement, numerical values just name the attribute uniquely. No ordering of the cases is implied.
The word nominal means in name.
Numbers representing nominal level data can only be used to classify or categorize. Numbers have no arithmetic properties and act only as labels. Examples of nominal level variables include:
- Sex (categories of male/female)
- Ethnicity (categories including African, Latino, White, Asian, etc.)
- Religion (Protestant, Catholic, Jewish, Moslem, Hindu, etc.)
- Place of birth (Paris, London, Seattle, Abuja, Taiwan)
This is an example of a question that would result in nominal data:
Which of the following political parties do you most identify with?
- Democrat
- Republican
- Independent
- Green
The resulting response data would only be used to classify the respondent, not to make value judgment. Additional types of variables that can produce nominal-level data include: location, telephone number, employment identification, area codes, etc.
Ordinal Level
Ordinal-level data measurement provides more information than the nominal level. Instead of simple identification, ordinal-level measurement can be used to rank or order objects.
The word ordinal means in order.
