Theory Lunch Seminar
— 1:00pm
Location:
8102
-
Gates and Hillman Centers
Speaker:
SIDDHARTH PRASAD
,
Ph.D. Student, Computer Science Department, Carnegie Mellon University
https://sid-prasad.github.io/
New Sequence-Independent Lifting Techniques for Cutting Planes and When They Induce Facets
Sequence-independent lifting is a procedure for strengthening valid inequalities of an integer program. We generalize the sequence-independent lifting method of Gu, Nemhauser, and Savelsbergh (GNS lifting) for cover inequalities and correct an error in their proposed generalization.
We obtain a new sequence-independent lifting technique — piecewise-constant (PC) lifting — with a number of interesting properties. We derive a broad set of sufficient conditions under which PC lifting is facet defining. To our knowledge, this is the first characterization of facet-defining sequence-independent liftings that are efficiently computable from the underlying cover.
Finally, we demonstrate via experiments that PC lifting can be a useful alternative to GNS lifting. We test our new lifting techniques atop a number of novel cover cut generation routines, which prove to be effective in experiments with CPLEX.
Event Website:
https://www.cs.cmu.edu/~theorylunch/
For More Information:
In Person