Seminar

Toric Ideals of Graphs

Abstract:

Toric ideals are a class of binomial ideals with many applications including to integer programming and algebraic statistics. One can associate a toric ideal to a finite simple graph by taking the kernel of the monomial map which sends the edges of the graph to the product of their endpoints. In this talk I will discuss some algebraic properties of toric ideals of graphs, focusing particularly on the Castelnuovo-Mumford regularity which is an invariant which measures the complexity of the relations among the generators of the ideal.
 

Making matrix factorization (more) useful

Matrix factorization features in many high dimensional data analysis problems. Typically, factorization methods are used to reduce the dimensionality of data and to visualize its structure. Factorization methods can also be viewed as models for whatever process is actually generating the data represented by the matrix. However, unlike for dimensionality reduction or visualization, success at this third goal is highly dependent on the specific factorization technique used.