https://doi.org/10.1351/goldbook.D01572
A statistical quantity indicating the number of values which could be arbitrarily assigned within the specification of a system of observations. For simple @R05300@, with \(n\) measurements and one estimated parameter (the mean), \(\nu =n- 1\). More generally, for multivariable computations, the number of degrees of freedom equals the number of observations minus the number of fitted parameters.