1. A method of producing a multivariate prediction model for predicting a property of a sample using a target spectrometer, based in part upon data measured by a reference spectrometer, the method comprising: producing property data by measuring said property for each of a plurality of calibration samples; for each calibration sample, producing a reference spectrometer response by making a plurality of measurements using the reference spectrometer; for each transfer sample in a subset of the calibration samples, producing a target spectrometer response by making a plurality of measurements using the target spectrometer; using the reference spectrometer responses for the calibration samples, the target spectrometer responses for the transfer samples, and the property data, producing estimates of the responses of the target spectrometer to the calibration samples; and producing a multivariate prediction model for the target spectrometer by combining the estimates of the responses of the target spectrometer to the calibration samples with the property data.