Thanks for visiting NZMaths.
We are preparing to close this site and currently expect this to be in June 2024
but we are reviewing this timing due to the large volume of content to move and
improvements needed to make it easier to find different types of content on
Tāhūrangi.
We will update this message again shortly.
For more information visit https://tahurangi.education.govt.nz/updates-to-nzmaths
A measure of spread for a distribution of a sample of numerical values that determines the degree to which the values differ from the sample mean.
It is calculated by the average of the squares of the deviations of the values from their sample mean.
The positive square root of the sample variance is equal to the sample standard deviation.
It is recommended that a calculator or software is used to calculate the sample variance. On a calculator the square of the standard deviation will give the variance.
A common symbol for the sample variance is s2.
The sample variance is a (sample) statistic and is therefore an estimate of the population variance.
See: measure of spread, sample standard deviation, variance
Curriculum achievement objectives references
Statistical investigation: Levels (7), (8)
