Which of these constructs can not be measured using a ratio scale?

Which of these constructs can not be measured using a ratio scale?

• A. Time
• B. Weight
• C. Temperature
• D. Distance

Answer: (C)

The key idea here is what makes a measurement scale a ratio scale: it has a true zero point (absence of the quantity) and equal intervals, so you can meaningfully compare magnitudes and form true ratios. Time, weight, and distance all have true zeros and equal intervals, so you can say one is twice as long, or four times as heavy, or twice as far, which fits a ratio scale. Temperature in the common scales (Celsius or Fahrenheit) does not have a true zero that means “none of the temperature.” Because zero degrees in these scales doesn’t represent the absence of temperature, you can’t meaningfully interpret ratios (like 100 vs 50) as indicating a true proportional difference. Therefore, temperature is not measured on a ratio scale in typical contexts. If you used the Kelvin scale, there is a true zero and it would be ratio, but the construct in this item is best viewed as not ratio.

The key idea here is what makes a measurement scale a ratio scale: it has a true zero point (absence of the quantity) and equal intervals, so you can meaningfully compare magnitudes and form true ratios.

Time, weight, and distance all have true zeros and equal intervals, so you can say one is twice as long, or four times as heavy, or twice as far, which fits a ratio scale.

Temperature in the common scales (Celsius or Fahrenheit) does not have a true zero that means “none of the temperature.” Because zero degrees in these scales doesn’t represent the absence of temperature, you can’t meaningfully interpret ratios (like 100 vs 50) as indicating a true proportional difference. Therefore, temperature is not measured on a ratio scale in typical contexts. If you used the Kelvin scale, there is a true zero and it would be ratio, but the construct in this item is best viewed as not ratio.