Ratio scale with true zero – UGC NET Question

A ratio scale has all the properties of an interval scale—equal intervals between values—and, in addition, a true zero point that indicates the complete absence of the measured attribute. This allows statements such as one value being twice or half of another to be meaningful. Examples include height, weight and reaction time. Because the stem highlights equal intervals, a true zero and meaningful ratios, it is describing a ratio scale.

Option A:
Interval scales, such as temperature in Celsius, have equal intervals but lack a true zero point, which makes ratio statements (like “twice as hot”) conceptually problematic. Therefore, interval is not sufficient to capture the “true zero and meaningful ratios” criterion given in the question.

Option B:
Ratio scales permit the full range of mathematical operations, including addition, subtraction, multiplication and division. This rich set of properties enables powerful statistical analyses and interpretable comparisons. These features match the description in the stem, so ratio is the correct completion.

Option C:
Nominal scales classify data into categories without order or quantitative meaning, making arithmetic operations and ratio statements inappropriate. They lack both equal intervals and a true zero, so nominal cannot be the answer.

Option D:
Ordinal scales indicate order among categories but do not assume equal differences between ranks, and they lack a true zero point. While they allow ranking, they do not support meaningful ratio comparisons, making ordinal an incorrect option for the stem’s description.