Value association are def-use associations whose computed values may have changed because of program edit and therefore require testing. For example, consider the following code segment:
... 1. X=2; /* replace with X=3; */ 2. if (A > 1) then 3. Y = X + 5; 4. else 5. Z = X - 5; 6. T = Y + 6; 7. U = Z + B; ...If statement 1 is replaced with ``X=3', no new def-use association are created. However, the def-use associations that depend on the new value of X are tested since they are affected by the change. Since both statement 3 and 5 use the definition of X in statement 1, def-use association (1,3,X) and (1,5,X) are value associations.