# GMX Energy with multiple error blocks

**URL:** <https://gromacs.bioexcel.eu/t/gmx-energy-with-multiple-error-blocks/3533>\
**Category:** User discussions\
**Created:** [January 23, 2022, 2:33am UTC](https://gromacs.bioexcel.eu/t/gmx-energy-with-multiple-error-blocks/3533 "2022-01-23T02:33:50Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![xadams](https://avatars.discourse-cdn.com/v4/letter/x/da6949/32.png) [@xadams](https://gromacs.bioexcel.eu/u/xadams)\
**Post date:** [January 23, 2022, 2:33am UTC](https://gromacs.bioexcel.eu/t/gmx-energy-with-multiple-error-blocks/3533/1 "2022-01-23T02:33:50Z")

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GROMACS version: 2020.2 cpu  
GROMACS modification: No

My understanding is that when I run gmx energy without -nbmin or -nbmax options, the error is calculated for a moving block average of 5. When I run over a range of options (e.g. -nbmin 5 -nbmax 50), still only a single error is reported so I was unsure what this value corresponded to. Naively, I expected the error value to increase, corresponding to the plot in figure 4.4 of a statistics resource ([4.8 Statistics](https://web.ornl.gov/~kentpr/thesis/pkthnode31.html)), however the error has decreased in all of the ranges I’ve run. Thanks in advance for your help.