Degree of Freedom

That measure of variability which merely expresses the number of options available within a variable or space. In a system with N states the degree of freedom is N. In statistics of the N cells of a table of probabilities only N-1 can be arbitrarily filled, the last being determined by the requirement that probabilities must add to 1 (see probability ), hence the degree or freedom is N-1. The measure of uncertainty may be interpreted as a logarithm ic measure of the degree of freedom logically or statistically available. (Krippendorff )