Reduced Costs in Pivot Strategy
In principle, a good pivot strategy would be to select whichever variable has the greatest reduced cost. However, the steepest edge might ultimately not be the most attractive, as the edge might be very short, thus affording only a small betterment of the object function value. From a computational view, another problem is that to compute the steepest edge, an inner product must be computed for every variable in the system, making the computational cost too high in many cases. The Devex algorithm attempts to overcome the latter problem by estimating the reduced costs rather than calculating them at every pivot step, exploiting that a pivot step might not alter the reduced costs of all variables dramatically.
Read more about this topic: Reduced Cost
Famous quotes containing the words reduced, costs, pivot and/or strategy:
“Love is a taste for prostitution. In fact, there is no noble pleasure that cannot be reduced to Prostitution.”
—Charles Baudelaire (1821–1867)
“It is commonly said by farmers, that a good pear or apple costs no more time or pains to rear, than a poor one; so I would have no work of art, no speech, or action, or thought, or friend, but the best.”
—Ralph Waldo Emerson (1803–1882)
“The seagull’s wings shall dip and pivot him,
Shedding white rings of tumult, building high
Over the chained bay waters Liberty—
Then, with inviolate curve, forsake our eyes”
—Hart Crane (1899–1932)
“Our strategy in going after this army is very simple. First we are going to cut it off, and then we are going to kill it.”
—Colin Powell (b. 1937)