CalibrationReport CV-RMSE and NMBE computation

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asked 3 years ago

rimas-maalka
41 ●3

updated 3 years ago

__AmirRoth__

4446 ●5 ●17 http://bleedinggreenna...

In the UtilityBill measure, the formulas for computing NMBE and CV-RMSE include an 'n-1' rather than just an 'n' in the denominator. For example:

Source: https://github.com/NREL/OpenStudio/bl...

result = 100.0 * std::pow(squaredError / (n - 1), 0.5) / ybar;
result = 100.0 * (sumError / (n - 1)) / ybar;

Why doesn't the formula just use 'n' as described in the definition, e.g. https://www.kw-engineering.com/how-to...

Thank you

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answered 3 years ago

macumber

12028 ●23 ●21 http://automaticmagic.com/

In this case, when you are estimating the variance you don't know what the real mean is so you have to use an estimate of the mean instead of the true mean. Estimating the mean reduces the degrees of freedom (number of samples) by one so you use N-1 instead of N which results in a slightly larger estimate of the variance. This link might help a bit:

https://stats.libretexts.org/Bookshel...

link

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Asked: 3 years ago

Seen: 304 times

Last updated: Nov 17 '21

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CalibrationReport CV-RMSE and NMBE computation