The Variable Precision Rough Set Model (VPRS) is an extension of the origin
al rough set model. This extension is directed towards deriving decision ta
ble-based predictive models from data with parametrically adjustable degree
s of accuracy. The imprecise nature of such models leads to quite significa
nt modification of the classical notion of decision table. This is accompli
shed by introducing the idea of approximation region-based, or probabilisti
c decision table which is a tabular specification of three, in general unce
rtain, disjunctive decision rules corresponding to rough approximation regi
ons: positive, boundary and negative regions. The focus of the paper is on
the extraction of such decision tables from data, their relationship to con
junctive rules and probabilistic assessment of decision confidence with suc
h rules.