# Glossary:RF matrix

- RF matrix
- a matrix that holds all R-Factor values, both measured and theoretical (i.e. those that could not be measured yet). R-Factors are arranged in rows of repetition category (i.e. the measure of memory stability) and columns of A-Factor (i.e. the measure of item difficulty). You can see your
**RF matrix**with**Toolkit : Statistics : Analysis : Matrices : RF matrix**