Poor linear relaxation

Dear users,
I have a MIP problem whose linear relaxation is very poor. Observe the report of CPLEX below:


(Gap greater to 999.99%, then the symbol “–”).
Does have any parameter in CPLEX to set to improve these performance?
Many thanks.

This question is better suited for a forum like https://or.stackexchange.com.

You’re more likely to get help if you provide more information, such as the formulation of your problem.

By the looks of it, I’m guessing you may have some big-M type constraints. Read https://www.gurobi.com/documentation/9.0/refman/num_dealing_with_big_m_con.html You will probably get better performance by improving the formulation of your model, rather than searching for different solver parameters.

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