1. Principal component analysis -- 2. Multiple correspondence analysis -- 3. Factorial analysis of mixed data -- 4. Weighting groups of variables -- 5. Comparing clouds of partial individuals -- 6. Factors common to different groups of variables -- 7. Comparing groups variables and Indscal model -- 8. Qualitative and mixed data -- 9. Multiple factor analysis and Procrustes analysis -- 10. Hierarchial multiple factor analysis -- 11. Matrix calculus and Euclidean vector space.