Hi, I have a general question about curve fitting within relax. Let's say I proceed to curve fitting for some relaxation rates (exponential decay) and that I have a duplicate delay for error estimation. ======== delays 0.01 0.01 0.02 0.04 ... ======== Will the mean value (for delay 0.01) be used for curve fitting and rate extraction ? Or will both values at delay 0.01 be used during curve fitting, hence giving more weight on delay 0.01 ? In other words, will the fit only use both values at delay 0.01 for error estimation or also for rate extraction, giving more weight for this duplicate point ? How is this handled in relax ? Instinctively, I would guess that the man value must be used for fitting, as we don't want the points that are not in duplicate to count less in the fitting procedure... Am I right ? Thanks for clarifying this... Séb