I believe you talk about the section about normalized RMSE (nRMSE). The nRMSE on the right side is 6% and thus lower than the nRMSE on the left side with 66%. T

I believe you talk about the section about normalized RMSE (nRMSE). The nRMSE on the right side is 6% and thus lower than the nRMSE on the left side with 66%. The lower the nRMSE the better. So I believe the article is correct. However it's always important to not only look at one performance metric but a bundle, e.g. including R2 for the correlation to make a good judgement of a sensor quality. We covered some of the basics in an earlier article [1]. [1] https://www.airgradient.com/blog/sensor-performance-precision-reproducibility-accuracy/ https://www.airgradient.com/blog/sensor-performance-precisio...