Sample Variance
Given a (random) sample
Notes:
- When describing features of a data set, the sample variance is used as a measure of variability for a data distribution which is not highly skewed, provided extreme values are not present.
- When making statistical inference, the sample variance is used as a point estimator of the variance of a normal distribution.
- The sample standard deviation is obtained by taking the (positive) square root of the sample variance.
- Note that
