Equating laboratories: modelling and analysis

Efficient world trade requires that manufacturers in one country have confidence that their product will meet specifications that are verified by purchasers in another country. But these trading partners rely upon different national metrology laboratories to calibrate their equipment, and there is detectable divergence between their measurement systems. This paper describes statistical methods that enable one to use data from a network of artifact comparisons to estimate the measurement functions at each participating laboratory. These methods cannot determine which laboratory is most accurate, but do allow one to predict the value that a given laboratory would obtain on an artifact from the value measured at another laboratory in the comparison network