Unbiased variance

Unbiased variance is a measure of the dispersion of data, used in particular when estimating the variability of a population from sample data. Specifically, it is a numerical value that shows how widely the measured values of a variable are spread. It is calculated by finding the mean of the squared deviations of each measured value from the average and dividing that value by the number of data points. By using n-1 (the number of samples minus 1) as the denominator, unbiased variance maintains unbiasedness. Using this measure helps in understanding the characteristics of a data distribution and provides an important foundation for statistical analysis.