Tools for Modeling Validation Process: The Dark Side ...

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The Dark Side of LP. What can go wrong in the process of building a Linear Programming (LP) model? Potential pitfalls exist which affect any LP application; ...
Tools for Modeling Validation Process: The Dark Side of LP What can go wrong in the process of building a Linear Programming (LP) model? Potential pitfalls exist which affect any LP application; therefore, the decisionmaker and the analyst should be cognizant of deficiencies of LP at the modeling stage.

 

1. Introduction 2. Unboundedness 3. Multiple Optimal Solutions (Innumerable optimal solutions) 4. No Solution (Infeasible LP) 5. Degeneracy 6. Degeneracy and the Dual (shadow) Prices 7. Shadow Price Might Have Wrong Sign 8. Redundancy Among the Constraints 9. Identification of Unbounded Feasible Regions 10. LP with no Vertex 11. LP With Unbounded, and Multiple Bounded Optimal Solutions 12. On the Basic and Nonbasic Decision Variables 13. LP Without Any Interior, and Boundary Solutions 14. Optimal Solution Generated by One LP Package Is Not Obtainable by the Other 15. Does the Optimal Simplex Tableau Give the Dual Solution? 16. Solution to an Integer LP May Not Be One of the Integer Vertices 17. Conversion to the Standard Form May Distort the Feasible Region 18. Removal of Equality Constraints by Substitution May Change the Problem 19. Misinterpretation of the Shadow Price 20. Is the Shadow Price Always Nonnegative? 21. Alternative Shadow Prices 22. The Cost Sensitivity Range by Grapical Method 23. More-for-less & Less-for-more Situations 24. JavaScript E-labs