weka中的Jrip輸出

Question

我正在對weka進行比較研究。使用一些評估標準，如;平均條件數量。

avg number of condition = number of conditions in the antecedent part/
          number of all generated rules 

，但我得到JRIP算法的輸出如下：

(Wifes_education = 4) and (Number_of_children_ever_born >= 3) and (Wifes_age >= 34) and (Wifes_age <= 42) => Contraceptive_method_used=2 (141.0/56.0) 
(Wifes_education = 4) and (Number_of_children_ever_born >= 3) and (Wifes_age >= 29) and (Wifes_age <= 48) and (Wifes_age >= 44) => Contraceptive_method_used=2 (53.0/24.0) 
(Wifes_age <= 35) and (Number_of_children_ever_born >= 3) => Contraceptive_method_used=3 (377.0/171.0) 
(Wifes_age <= 30) and (Number_of_children_ever_born >= 1) and (Wifes_age <= 22) => Contraceptive_method_used=3 (122.0/59.0) 

**=> Contraceptive_method_used=1 (780.0/316.0)** 
Number of Rules : 5 

怎麼樣的最後一條規則（粗體規則）？它沒有先行部分！ 我如何獲得最後一條規則的條件數量？

Answer 1

最後一條規則（隱式）條件「捕獲」其他規則未涵蓋的所有內容。它的條件是「其他」。