Which scale has ordered categories with equal intervals but no true zero?

Which scale has ordered categories with equal intervals but no true zero?

• A. Interval Scale
• B. Nominal Scale
• C. Ordinal Scale
• D. Ratio Scale

Answer: (A)

Think about how numbers store information about a quantity. In an interval scale, the numbers are ordered and the gaps between consecutive values are equal, so differences are meaningful. But there isn’t a true zero point that means “none” of the quantity, so you can’t interpret ratios. For example, Celsius temperature has equal increments (the difference from 20 to 30 is the same size as from 30 to 40), but 0°C does not signify no temperature, so you can’t say 40°C is twice as hot as 20°C. This distinguishes it from a ratio scale, which also has equal intervals but includes a true zero, allowing meaningful ratios (like height or weight). It’s different from ordinal scales, where values are ordered but the gaps between them aren’t guaranteed to be equal, and from nominal scales, where categories have no inherent order at all. Therefore, the described properties point to the interval scale.

Think about how numbers store information about a quantity. In an interval scale, the numbers are ordered and the gaps between consecutive values are equal, so differences are meaningful. But there isn’t a true zero point that means “none” of the quantity, so you can’t interpret ratios. For example, Celsius temperature has equal increments (the difference from 20 to 30 is the same size as from 30 to 40), but 0°C does not signify no temperature, so you can’t say 40°C is twice as hot as 20°C.

This distinguishes it from a ratio scale, which also has equal intervals but includes a true zero, allowing meaningful ratios (like height or weight). It’s different from ordinal scales, where values are ordered but the gaps between them aren’t guaranteed to be equal, and from nominal scales, where categories have no inherent order at all.

Therefore, the described properties point to the interval scale.