Comparison of results from repeated observations. Top panel of each sub-figure: differences between the results obtained using GES or FS data based on either GIRAFFE or UVES. Bottom panel of each sub-figure: differences between the results obtained using either UVES or GIRAFFE data. Two cases are considered: only GES data or observations taken from a different source (FS or GES). All the differences are expressed as GES minus FS and UVES minus GIRAFFE. The dotted curve is a normal distribution with a variance set to the nominal random uncertainty.