[AMPL 24764] MIPgap interpretation for a Minimization problem

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Hi everyone,

I am struggling a bit with the MIPgap interpretation of a minimization problem. I am trying to minimize the total wastage space inside a container.

My questions are as follows:

  1. The absolute gap is absmipgap=5.1717e+10 and my objective value is objVal = 2.45542e+10. Does this mean that if an optimal solution can be found, the optimal solution will be (2.45542e+10 - 5.1717e+10), which does not make sense at all because it is negative. there should not exist negative volume.

  2. How is it possible that the relative gap could be greater than 1? relmipgap=2.10624

Is there something that I am missing?

The solver I am using is HiGHS. Please kindly find a snippet of the returned result below.

HiGHS 1.5.1: cvt:bigM=16000
lim:time=300
mip:return_gap=2
Warning code 1 for call Highs_run(lp())
HiGHS 1.5.1: time limit
1.55039e+06 simplex iterations
14406 branching nodes
absmipgap=5.1717e+10, relmipgap=2.10624

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This question was also posted in the AMPL Discourse Forum, and it has been answered there.