You can use mean as a measure of central tendency for what scales?

You can use mean as a measure of central tendency for what scales?

• A. Ratio and Interval
• B. All scales
• C. Nominal
• D. Ordinal

Answer: (A)

Mean relies on arithmetic operations that assume equal spacing between consecutive values and, in the case of ratio scales, a true zero. This makes it appropriate for interval data (where differences are meaningful but there isn’t a true zero) and for ratio data (where both differences and ratios are meaningful and zero represents none of the quantity). For nominal scales, numbers are just labels with no meaningful distance between them, and for ordinal scales there is order but not necessarily equal intervals between ranks, so averaging these values would not have a meaningful interpretation. Therefore the mean is used with interval and ratio data.

Mean relies on arithmetic operations that assume equal spacing between consecutive values and, in the case of ratio scales, a true zero. This makes it appropriate for interval data (where differences are meaningful but there isn’t a true zero) and for ratio data (where both differences and ratios are meaningful and zero represents none of the quantity). For nominal scales, numbers are just labels with no meaningful distance between them, and for ordinal scales there is order but not necessarily equal intervals between ranks, so averaging these values would not have a meaningful interpretation. Therefore the mean is used with interval and ratio data.