When should the Crossover Parameter be used?

[Andrew B. Martin]

Hello,

I'm looking for some information on when its preferable to have the first push phase be primal versus dual when using the Barrier method on LP.

--Andrew

[Tobias Achterberg]

This is hard to answer. I think you just have to try whether one setting gives a
consistent benefit over the other for your problem class.

Tobias

[Andrew B. Martin]

Thanks, Tobias.

I suppose if there were general properties of a problem class that made it amenable to the first push phase being primal or dual, then Gurobi would be able to determine that on its own.

[Tobias Achterberg]

The automatic choice tries to guess the superior approach using statistics like
density of columns and the ratio of number of columns to rows. But it may happen
that a manual setting is superior for certain problem classes. Thus, as I said,
you have to try it experimentally.

Tobias