真心求助 og-171

oldreaper

171. a recent report determined that although only three percent of drivers on maryland
highways equipped their vehicles with radar detectors, thirty-three percent of all vehicles
ticketed for exceeding the speed limit were equipped with them. clearly, drivers who equip
their vehicles with radar detectors are more likely to exceed the speed limit regularly than
are drivers who do not.
the conclusion drawn above depends on which of the following assumptions?
(a) drivers who equip their vehicles with radar detectors are less likely to be ticketed for
exceeding the speed limit than are drivers who do not.
(b) drivers who are ticketed for exceeding the speed limit are more likely to exceed the
speed limit regularly than are drivers who are not ticketed.
(c) the number of vehicles that were ticketed for exceeding the speed limit was greater
than the number of vehicles that were equipped with radar detectors.
(d) many of the vehicles that were ticketed for exceeding the speed limit were ticketed
more than once in the time period covered by the report.
(e) drivers on maryland highways exceeded the speed limit more often than did drivers on
other state highways not covered in the report.

Answer: B
以前的帖子都看了，解释都不令人信服

assumption 的解法要求[not] A >> [not] B, 以前的帖子都没人说推论的过程，希望高人指点

albert

notice the GAP between evidence and conclusion in the passage...
evidence tell us that cars equipped with radar receive more ticket than those without radar
conclusion is that car equipped with radar are more likely to exceed speed limit..

there is a GAP between receiving tickets and exceeding speed limit..the assumption is a bridge to connect such jump...

good luck!

oldreaper

感谢回贴， 楼上的解释和陈向东说的一样，可以理解，关键是把答案取非，怎么能推出原推论不成立??

albert

以下是引用oldreaper在2003-8-22 10:07:00的发言：
感谢回贴， 楼上的解释和陈向东说的一样，可以理解，关键是把答案取非，怎么能推出原推论不成立??

without the GAP, we can't safely draw the conclusion...
could you tell me why you think that the conclusion can still hold without the assumption??

oldreaper

这道题我想通了，不过跟你的想法有些不同，我原来认为结论和你的一样是
>>conclusion is that car equipped with radar are more likely to exceed speed limit[装了雷达的车更容易超速]
按照这个结论将答案取非“被开了罚单的司机不比没被开罚单的司机容易超速”，则个前提和结论没有必然联系，即直接推出。当然这里有可能性，但是按照ETS的逻辑思维前提与结论要能直接推出，这是逻辑，否则通过一番论证再得出答案，那是哲学。所以按早我以前的这种想法肯定有理解上的问题。
但是经过仔细研究结论，在以前的一个铁字的提示下明白结论是
drivers who equip their vehicles with radar detectors are more likely to exceed the speed limit [ regularly ] than are drivers who do not.
要注意我扩起来的 regularly， 这里强调了一个频率，即结论是：车装了雷达的司机比车没装雷达的司机更可能经常超速。所以修正前面取非后的前提：被开了罚单的司机不比没被开罚单的司机更可能经常超速。也就是说所有的司机超速的频率性都是一样的，当让也推出结论部成立

而且这样理解，其他的答案界可以被否定。
另外，新东方讲座中提到，做assume题时可以利用，不取非加强/取非削弱的方法可以应用，但都不能保证答案的完全正确，这点我本人研究了一些体，只有取非导致原结论部成立的，或者根据结论可以直接推出前提成立，这种方法是完全有把握的。关于寻找前提与假设之间的联系的方法就更难控制了，这属于一个感觉的高层境界，但却不利于我们来检验答案的正确性。
谢谢大家，愿与你们分享