Which statement describes interval measurement?

Which statement describes interval measurement?

• A. It shows ordinal positions with equal intervals between scores.
• B. It has a true zero point.
• C. It relies on nominal categories only.
• D. It ranks data but does not indicate equal intervals.

Answer: (A)

Interval measurement means the values are ordered and the distances between adjacent values are equal, so differences are meaningful. The key property is equal intervals, with a zero point that is arbitrary, meaning you can add or subtract but not meaningfully form ratios. The statement that describes interval measurement captures this: it conveys both ordering and equal spacing between scores. The idea of a true zero belongs to a ratio scale, not interval. Nominal data have categories without order, and ordinal data have order without guaranteed equal intervals.

Interval measurement means the values are ordered and the distances between adjacent values are equal, so differences are meaningful. The key property is equal intervals, with a zero point that is arbitrary, meaning you can add or subtract but not meaningfully form ratios. The statement that describes interval measurement captures this: it conveys both ordering and equal spacing between scores. The idea of a true zero belongs to a ratio scale, not interval. Nominal data have categories without order, and ordinal data have order without guaranteed equal intervals.