AI engineering glossary · Statistics inference
What is degrees of freedom?
Degrees of freedom (also called df): The number of values in a calculation that are free to vary once constraints are fixed. It sets the exact shape of reference distributions such as the t and chi-square, and is often n - 1 or n minus the number of fitted parameters.
Degrees of freedom: an example
With 10 observations and a known average, only 9 values can vary freely, so a one-sample t-test uses 9 degrees of freedom.
Related terms
More Statistics inference terms
- Difference-in-differences
- Effect size
- Efficiency
- Estimator
- F-test
- False discovery rate
- Family-wise error rate
- Fisher information
Where you learn it
Degrees of freedom is part of the AI Engineering Program, which teaches it with notes, a hands-on lab and an exam. The first lesson is free.