In order to define or measure the language proficiency of a person, particularly the degree of flawlessness in the pronunciation, and/or to find out the linguistic background and identity of a person, the person's speech is compared with a selected reference language. This is achieved by applying autocorrelation and/or pattern recognition and/or signal processing and/or other corresponding methods for identifying and registering such sound elements and features that are typical of the reference language and occur repeatedly in the reference language speech sample. On the basis of the obtained linguistic profile of the reference language, corresponding sound elements and features are searched in the speech of the person, and there is calculated how many of the sound elements and features of the reference language linguistic profile the person substitutes with such sound elements or features that deviate from the reference language, and the substitute sound elements and features are defined.
METHOD OF LINGUISTIC PROFILING