How is variance defined in statistical terms?

Variance in statistical terms is defined as the square of the standard deviation. It measures the degree of dispersion or spread in a set of data points. When calculating variance, one looks at how each data point differs from the mean of the dataset and subsequently squares those differences. This squaring of the differences is crucial because it ensures that negative differences do not cancel out positive ones, providing a true reflection of variability.

By squaring the standard deviation, we can express that variability in a consistent unit, which is essential for statistical analysis. Variance, therefore, provides a quantitative assessment of how much the values in a dataset typically deviate from the mean value, indicating the extent of spread or concentration of the data.