What term describes the average squared distance from the mean in a population or sample?

The term that describes the average squared distance from the mean in a population or sample is variance. Variance quantifies how much the values in a dataset differ from the mean, specifically by taking the average of the squared differences. By squaring the differences before averaging, variance emphasizes larger deviations from the mean, making it a crucial measure in statistics for understanding data dispersion.

This measure is foundational when analyzing data, as it provides insights into the distribution's spread and helps in further statistical computations like standard deviation, which is simply the square root of variance. Variance plays a pivotal role in various statistical analyses, including hypothesis testing and regression analysis, allowing for a deeper understanding of data behavior.