# \[AMPL 24764\] MIPgap interpretation for a Minimization problem

**URL:** <https://discuss.ampl.com/t/ampl-24764-mipgap-interpretation-for-a-minimization-problem/713>\
**Category:** Google Group Mirror\
**Created:** [September 3, 2023, 11:12pm UTC](https://discuss.ampl.com/t/ampl-24764-mipgap-interpretation-for-a-minimization-problem/713 "2023-09-03T23:12:42Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Hung-Yu\_Yang](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.ampl.com/hung-yu_yang/32/388_2.png) [@Hung-Yu\_Yang](https://discuss.ampl.com/u/Hung-Yu_Yang)\
**Post date:** [September 3, 2023, 11:12pm UTC](https://discuss.ampl.com/t/ampl-24764-mipgap-interpretation-for-a-minimization-problem/713/1 "2023-09-03T23:12:42Z")

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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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**Author:** ![AMPL\_Google\_Group](https://avatars.discourse-cdn.com/v4/letter/a/9dc877/32.png) [@AMPL\_Google\_Group](https://discuss.ampl.com/u/AMPL_Google_Group)\
**Post date:** [September 4, 2023, 2:43pm UTC](https://discuss.ampl.com/t/ampl-24764-mipgap-interpretation-for-a-minimization-problem/713/2 "2023-09-04T14:43:14Z")

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This question was also posted in the [AMPL Discourse Forum](https://discuss.ampl.com), and it has been answered there.
