Influence of correlation on the assessment of measurement result compatibility over a dynamic range

Comparison of measurement results obtained by different measuring equipment on the same reference object is a key element in equipment qualification. The paper discusses an approach for an integrated assessment of a series of comparison measurements taken on more than one (i.e. many) reference object(s). The approach accounts for the fact that measurements taken by one (and also by the other) instrument on a series of ideally independent objects are nevertheless partially correlated due to common uncertainty contributions arising from the measurement process. The approach is exemplified for international comparisons using a (travelling) transfer instrument for the comparison of national instrument standards with a reference standard over a range of measured ozone mole fractions.