Which measurement type is primarily concerned with ranking variables without fixed intervals?

The measurement type that is primarily focused on ranking variables without fixed intervals is known as ordinal measures. Ordinal scales allow researchers to order or rank data points based on some criteria; however, the distances or differences between these ranks cannot be precisely quantified. For instance, in a survey where respondents rank their satisfaction on a scale from "very dissatisfied" to "very satisfied," the responses can be ordered, but the difference between "satisfied" and "very satisfied" does not have a specific numerical value attached to it. This characteristic allows for the ranking of items but does not provide equal intervals between the ranks, distinguishing ordinal measures from other types of scales like interval or ratio, where the intervals are consistent and meaningful.

In contrast, nominal measures categorize data without any ranking or order, while interval and ratio measures involve fixed intervals or a true zero, which allows for more detailed mathematical calculations. In summary, ordinal measures are uniquely situated between these other forms of measurement by allowing for ranking but lacking the consistent intervals that are essential for more precise measurement types.