GLOBAL AND DISCRETE CONSTRAINT ACTIVITY

The concept of constraint activity, widely used throughout the optimiz ation literature, is extended and clarified to deal with global optimi zation problems containing either continuous or discrete variables. Th e article presents definitions applicable to individual constraints an d discusses definitions for groups of constraints. Concepts are reinfo rced through the use of examples. The definitions are used to investig ate the ideas of optimization ''cases'' and monotonicity analysis as a pplied to global and discrete problems. Relationships to local optimiz ation are also noted.