Mumford's GIT quotient is one way to construct moduli spaces that parametrizes classes of algebro-geometric objects. It turns out there is an interesting structure on the set of unstable points discarded in the GIT quotient construction. In this talk I would aim to describe:
1. the stratification of the unstable points and its variation caused by different choice of linearizations;
2. wall and chamber decomposition analogous to Variation of Geometric Invariant Theory Quotient;
3.examples and results in the case of projective toric varieties.