What is the definition of the term that describes how much a variable's value differs from the mean or other benchmark?

The term that describes how much a variable's value differs from the mean or other benchmark is indeed "deviation." Deviation captures the difference between an individual data point and the mean of a dataset, which signifies how far away each observation lies from the central tendency. This measure allows statisticians to understand the spread and variability within the data set, as well as assess how representative the mean is of the overall data.

For context, the range refers to the difference between the maximum and minimum values in a dataset, but it does not provide insight into the differences of individual values from the mean. The error of the mean typically refers to the uncertainty associated with an estimated mean value, often represented by the standard error, which is not the same as measuring individual deviations. Average deviation, on the other hand, could refer to the average of the absolute deviations, but it is not a standard term like "deviation" and may not encompass the concept as clearly as the term "deviation" does.