Which measure is defined as the difference between the highest and lowest values in a dataset?

The measure defined as the difference between the highest and lowest values in a dataset is known as the range. The range provides a simple measure of how spread out the values are within the dataset by subtracting the smallest value from the largest value. This is particularly useful for gaining a quick understanding of the extent of variability present in the data.

In contrast, variance and standard deviation are measures of spread that involve calculations based on the average of the squared differences from the mean, making them more complex than simply identifying the highest and lowest values. The coefficient of variation, on the other hand, is a standardized measure of dispersion calculated as the ratio of the standard deviation to the mean, which also does not directly address the simple difference between maximum and minimum values. Thus, the range is the measure that best fits the definition provided in the question.