Standard deviation (σ) is the square root of variance
Standard deviation
Standard deviation (σ) is the square root of variance
Standard deviation measures the variation of values around their mean. It is denoted by the Greek letter σ (sigma) and is expressed in the same units as the data. Standard deviation is a crucial concept in statistics as it quantifies the amount of dispersion or spread in a dataset.
Example
If the mean of a dataset is 10 and the variance is 4, the standard deviation (σ) would be √4 = 2.
Remember this
Understanding standard deviation is essential for interpreting data variability and making informed decisions based on statistical analysis.
Text adapted from Wikipedia, licensed under CC BY-SA 4.0.
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