A method of formation of multivariate calibration models being steady against changes of properties being external conditions and/or measuring device characteristics and affecting measurement results from the measuring device, the method comprising - selecting a calibration set of samples with known secondary properties, wherein the secondary properties are the sample properties to be analyzed; - measuring primary properties of each of the samples of the calibration set on the measuring device, wherein the primary properties are the sample properties to be directly measured; - carrying out artificial alterations of at least one of the properties affecting the measurement results of the measuring device; - measuring the primary properties of at least one sample on the measuring device in a state altered this way, - forming a limited sample set for calculation of correcting relationships before carrying out the alterations, wherein the limited sample set consists of a much smaller number of samples than the calibration set, and wherein the samples are selected to provide essential distinctions in the measurement results in the range of all primary properties on the measuring device, both in the initial and in the altered state; - measuring the primary properties of each sample from this set on the measuring device before and after carrying out the alterations, characterized by - defining the correcting relationships by means of comparing the measurement results of the primary properties of the samples of the limited set obtained on the measuring device before carrying out the alterations with the measurement results of the primary properties of the same samples obtained on the measuring device in the state when the alterations are made, wherein this comparison is carried out using multivariate regression analysis methods; - transforming the measurement results of the primary properties of the samples of the calibration set by means of the obtained correcting relationships to a form corresponding to the form of measurements on the measuring device after the alterations; - complementing the measurement results of the primary properties of the calibration samples being obtained on the measuring device before the alterations to the primary properties measurement results of the samples of the calibration set being corrected to the altered state of the measuring device as mentioned above; - calculating the multivariate calibration model based on a set of the initial and corrected measurement results of the primary properties of the samples of the calibration set; and - carrying out verification of the multivariate calibration model, defining thereby quantitative parameters of the calibration validation, namely, at least one of the standard calibration error, the standard validation error and the standard cross-validation error. - selecting a calibration set of samples with known secondary properties, wherein the secondary properties are the sample properties to be analyzed; - measuring primary properties of each of the samples of the calibration set on the measuring device, wherein the primary properties are the sample properties to be directly measured; - carrying out artificial alterations of at least one of the properties affecting the measurement results of the measuring device; - measuring the primary properties of at least one sample on the measuring device in a state altered this way, - forming a limited sample set for calculation of correcting relationships before carrying out the alterations, wherein the limited sample set consists of a much smaller number of samples than the calibration set, and wherein the samples are selected to provide essential distinctions in the measurement results in the range of all primary properties on the measuring device, both in the initial and in the altered state; - measuring the primary properties of each sample from this set on the measuring device before and after carrying out the alterations, - defining the correcting relationships by means of comparing the measurement results of the primary properties of the samples of the limited set obtained on the measuring device before carrying out the alterations with the measurement results of the primary properties of the same samples obtained on the measuring device in the state when the alterations are made, wherein this comparison is carried out using multivariate regression analysis methods; - transforming the measurement results of the primary properties of the samples of the calibration set by means of the obtained correcting relationships to a form corresponding to the form of measurements on the measuring device after the alterations; - complementing the measurement results of the primary properties of the calibration samples being obtained on the measuring device before the alterations to the primary properties measurement results of the samples of the calibration set being corrected to the altered state of the measuring device as mentioned above; - calculating the multivariate calibration model based on a set of the initial and corrected measurement results of the primary properties of the samples of the calibration set; and - carrying out verification of the multivariate calibration model, defining thereby quantitative parameters of the calibration validation, namely, at least one of the standard calibration error, the standard validation error and the standard cross-validation error.