A simple model of the development of relations between ethnic groups is constructed. The method for the numerical identification of this model on the basis of data of quantitative observations is described. The following two modes are distinguished: the uncontrolled (autonomous) mode, which is characterized by the occurrence of sporadic surges of ethnocentrism that naturally die down, and the control mode. The autonomous part of the model is first identified, and, then, the control coefficients are found using the measured effect of the control. The mass media are used as a source of control actions. The preparation of scripts for radio broadcasts is described. The identification process for the autonomous part of the model is illustrated by an example.