  The purpose of this paper is to study entanglement of quantum states by means
of Schmidt decomposition. The notion of Schmidt information which characterizes
the non-randomness of correlations between two observers that conduct
measurements of EPR-states is proposed. In two important particular cases - a
finite number of Schmidt modes with equal probabilities and Gaussian
correlations- Schmidt information is equal to Shannon information. A universal
measure of a dependence of two variables is proposed. It is based on Schmidt
number and it generalizes the classical Pearson correlation coefficient. It is
demonstrated that the analytical model obtained can be applied to testing the
numerical algorithm of Schmidt modes extraction. A thermodynamic interpretation
of Schmidt information is given. It describes the level of entanglement and
correlations of micro-system with its environment
