A method of estimating a concentration of an analyte may include obtaining a plurality of in vivo estimation spectra, generating a plurality of noise detection models by varying a number of principal components based on the plurality of in vivo estimation spectra, comparing the generated plurality of noise detection models with a plurality of concentration estimation models for each number of principal components, extracting a noise spectrum and a concentration estimation model for use in estimating the concentration of the analyte based on the comparison, updating the extracted concentration estimation model based on the extracted noise spectrum, and estimating the concentration of the analyte by using the updated concentration estimation model and an in vivo estimation spectrum from among the plurality of in vivo estimation spectra.
