What is an example of nominal measurement?

Nominal measurement refers to a type of data that is categorized without a specific order or ranking among the categories. In this context, area codes serve as an excellent example of nominal measurement. Each area code represents a specific region or locality and is simply a label to identify different geographical areas. There is no inherent order or ranking among area codes; they are merely different categories used to distinguish locations.

To further clarify, weight categories involve a scale where weights can be compared and ranked, making them ordinal measurements. Temperature in Celsius is a quantitative measure that has a defined scale and can be manipulated mathematically, placing it in the interval or ratio category rather than nominal. Ranking of athletes introduces an order and hierarchy based on performance, which also classifies it as ordinal rather than nominal. Thus, area codes are distinctly nominal as they provide a way to categorize without any implied ranking or order.