What type of measurement is characterized by attaching names as labels to objects?

Nominal measurement is a type of measurement characterized by assigning names or labels to distinguish different categories or groups without implying any quantitative value or order among them. This form of measurement is used purely for identification purposes, where each category is mutually exclusive. For instance, when labeling individuals as "male" or "female," those labels serve to categorize respondents without revealing any information about the magnitude or ranking of the categories.

The key aspect of nominal measurement is that it allows for the classification of items into distinct groups based solely on names. There is no inherent rank or order; for example, the categories "red," "blue," and "green" represent purely qualitative identifiers without any numerical significance.

In contrast, ordinal measurement involves data that can be ordered but does not specify the distance between categories. Interval measurement includes ordered categories with equal distances but lacks a true zero point, while ratio measurement also has ordered categories, equal intervals, and a true zero point, which allows for a wider range of mathematical operations. Understanding these distinctions highlights why nominal measurement, characterized by naming groups, serves as the foundational level of measurement in research schemes.