Most of the content of these slides reflect results obtained jointly with Andrei Zelevinsky.
Other collaborators: A.Berenstein, F.Chapoton.

All of the files are PostScript.

1. Total positivity criteria and matrix factorizations (42 pages, in color)

• Planar networks
• Total positivity criteria
• Parametrizations of TP matrices
• Totally nonnegative varieties
• Generalizations to semisimple Lie groups

2. From double Bruhat cells to cluster algebras (29 pages)

• Double Bruhat cells
• Cluster algebras
• Further examples

3. Cluster algebras of finite type and generalized associahedra (44 pages)

• Finite type classification
• Associahedron and cyclohedron
• Generalized associahedra
• Classical types
• Catalan combinatorics of general type
• Associahedra as cluster complexes