classification rules

1. Criteria for choosing tests

The basic criterion for choosing a test to add to a rule is to find one that covers as many positive examples as possible, while covering as few negative examples as possible.

评估产生的规则需要同时考虑覆盖率( 2/2=100%? )和正确率。

2. 包含例外的规则

所产生的这些规则有个特点，即大多数的实例都被高层的规则所覆盖，而低层的规则正是代表例外。因此人们可以忽略所有深层结构而只关心前面的一二层便能对这些规则到底干什么能有非常清楚的认识。这正是包含例外规则的诱人之处。