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## Main Question or Discussion Point

Hello! I am a bit confused about the systematic errors in experiments. For example, say that a mass scale was not calibrated and indicates 1g bigger all the time and I want to publish a paper in which to quote some measurements made with that scale. Let's assume that the value obtained, without taking the systematic into account is ##250\pm 2##g, where the error here is statistical. In many papers I read (most of them in experimental particle physics) the errors have both statistical and systematic uncertainties, so if I am to follow that, I would quote my final result (once I realize my calibration problem) as ##250\pm(2)_{stat}\pm(1)_{sys}## g. So my question is, why can't I subtract 1 from my result and state it as ##249\pm 2## g? The calibration would affect just the mean, not the error. Also using ##\pm## for a statistical error seems a bit weird, given that I know the direction of the bias. So overall, my question is: once you state a systematic error in your result (in a paper), it means that you are aware of it and of the direction it creates the bias, so why not just correct the mean value and remain with just the statistical error? Or, at least, why not specify the direction of the systematic error, if you want to be fair and include it in the final result? Thank you!