Glossary:OF matrix

OF matrix

matrix of O-Factors for different levels of difficulty (expressed as A-Factor) and stability (expressed as repetition category). The OF matrix is used by SuperMemo Algorithms SM-5 through SM-15 in computing optimum intervals in spaced repetition. In the newest algorithms, the role of the 2-dimensional OF matrix is played by the 3-dimensional SInc[] matrix (with the added dimension of retrievability)