标题: 费费135 是求助第135题怎么做啊~！！ [打印本页] 作者: angelazhao1010 时间: 2010-8-15 17:14 标题: 费费135 是求助第135题怎么做啊~！！ 135. In a new police program, automobile owners in some neighborhoods whose cars are not normally driven between 1 A.M. and 5 A.M. can display a special decal in the cars’ windows and authorize police to stop the cars during those hours to check the drivers’ licenses. The theft rate for cars bearing such decals is much lower than had been usual for cars in those neighborhoods. If it is concluded from the statements above that automobile theft has been reduced by the program, which one of the following would be most important to answer in evaluating that conclusion? (A) Are owners who are cautious enough to join the program taking other special measures to protect their cars against theft? (B) In how many neighborhoods is the police program operating? (C) Are cars in neighborhoods that are actively participating in the program sometimes stolen during daylight hours? (D) Will owners who have placed decals on their cars’ windows but who find it necessary to drive between 1 A.M. and 5 A. M. Be harassed by police? (E) Are the neighborhoods in which the program has been put into effect a representative cross section of neighborhoods with respect to the types of automobiles owned by residents? 答案是A。 想问一下，E为什么不对呢，怎么解释啊作者: 2008115061 时间: 2010-8-15 17:33
要评估的对象是：是不是program导致了盗窃率的减少 找出其他原因就好了，A， 不多说了。 E的话，说想评估车种是不是在这个社区有代表性，和这个program本身关系不大，因为无论是什么车 都会贴label; 如果想说车种和偷窃也有关，那可能就是过分推理，没有A来的那么直接