In a method of estimating a component concentration of a mixture, and an
apparatus for performing the method, the method includes 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, and determining a
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 determined small group.