Patent ID: 7289912

Claim:
A method of estimating a component concentration of a mixture, comprising: generating a global calibration model with respect to a calibration data set using a concentration value determined by a plurality of independent variables including a predetermined specific component, a concentration of which is intended to be estimated, as a dependent variable; dividing the calibration data set into at least two small groups according to a value of the dependent variable and generating local calibration models for each of the at least two small groups using the calibration data set included in the divided at least two small groups; determining a relevant small group to which a spectrum of the mixture belongs and estimating a concentration of the specific component using a local calibration model of the relevant small group; and using the generated local calibration models to predict concentration values, wherein determining the relevant small group to which the spectrum of the mixture belongs includes using a concentration value of the specific component obtained by applying the global calibration model to the spectrum of the mixture.