已知:规则可信度为 r1:IF E1 THEN H1 (0.7) r2:IF E2 THEN H1 (0.6) r3:
已知:规则可信度为 r1:IF E1 THEN H1 (0.7) r2:IF E2 THEN H1 (0.6) r3:IF E3 THEN H1 (0.4) r4:IF (H1 AND E4)THEN H2 (0.2) 证据可信度为 CF(E1)=CF(E2)=CF(E3)=CF(E4)=CF(E5)=0.5 H1的初始可信度一无所知,H2的初始可信度CF0(H2)=0.3 计算结论H2的可信度CF(H2)。
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热搜:无名合同的法律适用规则为
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正确答案:×
由题意得到推理网络如图4.12所示。由于对H1的初始可信度一无所知,所以可以利用规则r1、r2、r3和合成法来求H1的可信度。①由规则r1、r2、r3,分别计算CF(H1):CF1(H1)=CF(H1,E1)×max{0,CF(E1)}=0.7×0.5=0.35CF2(H1)=CF(H1,E2)×max{0,CF(E2)}=0.6×0.5=0.3CF3(H1)=CF(H1,E3)×max{0,CF(E3)}=0.4×0.5=0.2②利用合成算法计算H1的综合可信度:CF1,2(H1)=CFl(H1)+CF2(H1)-CFl(H1)×CF2(H1)=0.35+0.3=0.35×0.3=0.545CF1,2,3(H1)=CF1,2(H1)+CF3(H1)-CF1,2(H1)×CF3(H1)=0.545+0.2-0.545×0.2=0.636③计算H2的可信度CF(H2),这时,由于已知H2的初始可信度,计算采用更新法。由规则r4和公式(4.5)可知:CF(H2)=CF0(H2)+CF(H2,H1∧E4)×CF(H1∧E4)-CF0(H2)×CF(H2,H1∧E4)×CF(H1∧E4)=0.3+0.2×min{CF(H1),CF(E4)}-0.3×0.2×min(CF(H1),CF(E4)}=0.3+0.2×min{0.636,0.5)-0.3×0.2×min{0.636,0.5}=0.3+0.2×0.5-0.3×0.2×0.5=0.37所以,所求得的H2的可信度更新值为CF(H2)=0.37
