What characterizes an interval scale in data measurement?

An interval scale is characterized by the fact that it not only establishes a meaningful order among values but also ensures that the exact differences between values are known and consistent. This means that on an interval scale, the intervals between the measurements are equal, allowing for the comparison of how much more one value is than another.

For instance, temperature measured in Celsius or Fahrenheit is a classic example of an interval scale. The difference between the temperatures of 20°C and 30°C is the same as the difference between 30°C and 40°C, providing precise and interpretable data regarding temperature changes.

In contrast to other measurement types, an interval scale does not possess a true zero point that indicates an absence of the quantity being measured (as seen in ratio scales). Therefore, interval scales do not support meaningful ratio comparisons, such as stating that one value is "twice" another. The focus on the known order and equal intervals is what distinctly identifies an interval scale.