@misc{AchterbergKochMartin, author = {Achterberg, Tobias and Koch, Thorsten and Martin, Alexander}, title = {Branching on History Information}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-6990}, number = {02-32}, abstract = {Mixed integer programs (\$MIPs\$) are commonly solved with branch and bound algorithms based on linear programming. The success and the speed of the algorithm strongly depends on the strategy used to select the branching variables. Today's state-of-the-art strategy is called \emph{pseudocost branching} and uses information of previous branchings to determine the current branching. We propose a modification of \emph{pseudocost branching} which we call \emph{history branching}. This strategy has been implemented in \$SIP\$, a state-of-the-art \$MIP\$ solver. We give computational results that show the superiority of the new strategy.}, language = {en} } @misc{AchterbergKochMartin, author = {Achterberg, Tobias and Koch, Thorsten and Martin, Alexander}, title = {MIPLIB 2003}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-8625}, number = {05-28}, abstract = {This paper reports on the fourth version of the Mixed Integer Programming Library. Since ({\sc miplib}) is to provide a concise set of challenging problems, it became necessary to purge instances that became too easy. We present an overview of the 27 new problems and statistical data for all 60 instances.}, language = {en} } @misc{MarchandMartinWeismanteletal., author = {Marchand, Hugues and Martin, Alexander and Weismantel, Robert and Wolsey, Laurence}, title = {Cutting Planes in Integer and Mixed Integer Programming}, url = {http://nbn-resolving.de/urn:nbn:de:0297-zib-4339}, number = {SC-99-44}, abstract = {This survey presents cutting planes that are useful or potentially useful in solving mixed integer programs. Valid inequalities for i) general integer programs, ii) problems with local structure such as knapsack constraints, and iii) problems with 0-1 coefficient matrices, such as set packing, are examined in turn. Finally the use of valid inequalities for classes of problems with structure, such as network design, is explored.}, language = {en} }