AI engineering glossary · Probability
What is SD (standard deviation)?
Standard deviation (also called SD): The square root of the variance, giving spread in the same units as the variable itself. For bell-shaped data, about 68% of values lie within one standard deviation of the mean and about 95% within two.
Standard deviation: an example
If delivery times average 30 minutes with a standard deviation of 5, most deliveries take between 25 and 35 minutes.
Related terms
More Probability terms
- Standard normal distribution
- Stationary distribution
- Stratified sampling
- Survivorship bias
- Systematic sampling
- Transition matrix
- Uniform distribution
- Union of events
Where you learn it
Standard deviation is part of the AI Engineering Program, which teaches it with notes, a hands-on lab and an exam. The first lesson is free.