With this general background, let us investigate the properties of LP and QP problems. 2.2 Linear Programming A linear programming problem is commonly:stated in the following manner. Maximize (Ll) c'x subject to the restriction that Ax < b (L2) (L2) x >0 where c and b are known vectors, A is a known matrix, and x is a vector of variable activities which are controlled by a decisionmaker. The constraints Ax < b and x > 0 mark off a set of points in a product space which represent the set of choices available to the decisionmaker due to technological, economic, and institutional constraints. The objective of the problem is to choose one point R which is in this set and which makes the product c'x as large as possible. The term c'x is the objective function which may, for example, represent net profit associated with the set of activities chosen. The necessary conditions for the saddle value solution of this LP problem can be stated as follows: (L3) c A 0 and (c A ) x = 0; (NL1) (L4) b Ax > 0 and (b- Ax) = 0; (NL2) and (L5) x> 0 and 5 > 0; (NL3). Condition (L4) states that the primal constraints must be satisfied and that for each non-binding constraint, the shadow price or dual activity associated with it must be zero. This concept is central to our discussion and should be considered carefully. In the context of LP,