How Accurate is Solver?

I want to compare two different optimal scenarios answers obtained from
Solver but they are quite close. I want to say, well scenario X's optimal
value is so and so larger than scenario Y's optimal value. For this I need to
understand how many decimal places are relevant in each answer. So I need to
understand what determines the accuracy of a Solver answer. Initially I
thought it was the Convergence setting but this is only for answers which
converge slowly. Not for answers which actually give the message 'Solver
found a solution'. Can anyone tell me exactly to how many decimal places I
can trust in a Solver answer?

Andy,

You can do a sensitivity analysis by changing the optimal value by a small amount and seeing how
that affects your calculated value - too much depends on your model to say anything definitive.

HTH,
Bernie
MS Excel MVP


"andysween" wrote in message
...
I want to compare two different optimal scenarios answers obtained from
Solver but they are quite close. I want to say, well scenario X's optimal
value is so and so larger than scenario Y's optimal value. For this I need to
understand how many decimal places are relevant in each answer. So I need to
understand what determines the accuracy of a Solver answer. Initially I
thought it was the Convergence setting but this is only for answers which
converge slowly. Not for answers which actually give the message 'Solver
found a solution'. Can anyone tell me exactly to how many decimal places I
can trust in a Solver answer?