Research Article

Knowledge Reduction Based on Divide and Conquer Method in Rough Set Theory

Table 9

The experimental results of 3 algorithms on KDDCUP99 data sets (<5 × 106 records).

Number of records C4.5 CART Our methods
RRate Tr Te RRate Tr Te RRate Tr Te

489843 0.9998 158 0.124 0.9997 386 0.031 0.9998 499 0.063
979686 0.9999 330 0.187 0.9998 1517 0.312 0.9998 1472 0.141
1469529 0.9999 706 0.312 0.9999 5851 5.554 0.9999 4026 0.156
1959372 0.9999 883 0.499 0.9999 6650 0.421
2449216 0.9999 1143 0.624 0.9999 11446 0.476
2939059 0.9999 1176 0.655 0.9999 14023 0.578
3428902 0.9999 1849 0.827 0.9999 35361 0.606
3918745 0.9999 2043 0.923
4408588 0.9999 2567 1.106
4898432 0.9999 2916 1.217