In order to improve the speed and efficiency of reduction algorithm of core influence attributes

a new core computation algorithm based on positive region is provided. The positive region based on radix sorting is used to get the positive region condition attributes set of decisionattributes and the condition attribute set which excludes one of the condition attributes of decision attribute positive region. Then the difference between the two radices of positive regions is calculated to judge whether the condition attribute is a core attribute

thereby all the condition attributes are judged and the required core is quickly acquired. The time complexity of the proposed algorithm is O(|C||U|). Experimental results show that the core computation time increases linearly with the increasing number of entries

and the computation time is only 0.6% of the contrastive algorithm when the entries is maximum. Meanwhile

it is shown that the algorithm is well suitable for various kinds of data sets.