Abstract: By considering the "multiple-valued" character in practical decision procedure, the interval-valued loss funcdons were induced to decision-theoretic rough set theory (DTRS) based on the 13ayesian decision theory. With respect to the minimum I3ayesian expected risk, a model of interval-valued decision-theoretic rough set theory was built The corresponding propositions and criteria of interval-valued decision-theoretic rough set theory were also analyzed. An example of oil investment was given to illuminate the proposed model in applications.

Key words: Decision-theoretic rough set theory, Probabilistic rough set theory, l3aycsian decision procedure, Interval-valued