Abstract
In this paper, we investigate rule induction from imprecise decision tables. Impresice decision tables are data tables whose decision attribute values are specified only imprecisely. We propose a rough set approach to imprecise decision tables. After treatment of imprecise decision attribute values is described, four rule induction schemas are proposed. For each rule induction schema, we apply LEM2-based rule induction algorithm by defining positive object set appropriately. The performances of the proposed rule induction algorithms are examined by numerical experiments.