Which data type has a true zero and allows multiplicative comparisons?

Which data type has a true zero and allows multiplicative comparisons?

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

Answer: (D)

Multiplicity and a true zero point are what allow ratio data to be compared by multiplication. Ratio data have a meaningful zero that means “none of the quantity,” so you can form ratios like twice as much, half as big, etc. Examples include height, weight, distances, or Kelvin temperature. Because the zero represents the absence of quantity, a value of 0 indicates no amount, and ratios are interpretable. The other data types don’t support these multiplicative comparisons. Nominal data are just categories with no order or magnitude. Ordinal data have order but not equal intervals, so you can't determine meaningful ratios. Interval data have equal intervals, but their zero is arbitrary (like Celsius), so you can add or subtract meaningfully but not form true ratios.

Multiplicity and a true zero point are what allow ratio data to be compared by multiplication. Ratio data have a meaningful zero that means “none of the quantity,” so you can form ratios like twice as much, half as big, etc. Examples include height, weight, distances, or Kelvin temperature. Because the zero represents the absence of quantity, a value of 0 indicates no amount, and ratios are interpretable.

The other data types don’t support these multiplicative comparisons. Nominal data are just categories with no order or magnitude. Ordinal data have order but not equal intervals, so you can't determine meaningful ratios. Interval data have equal intervals, but their zero is arbitrary (like Celsius), so you can add or subtract meaningfully but not form true ratios.