手敲OG11 Diagnostic Test-25 郁闷的题。。

感觉这是diagnostic里最难的一题，敲上来，大家讨论下吧

Tiger beetles are such fast runners that they can capture virtually any nonflying insect. However, when running toward an insect, a tiger beetle will intermittently stop and then, a moment later, resume its attack. Perhaps the beetles cannot maintain their pace and must pause for a moment's rest; but an alternative hypothesis is that while running, tiger beetles are unable to adequately process the resulting rapidly changing visual information and so quickly go blind and stop.

Which of the following, if discovered in experiments using moved prey insects, would support one of the two hypotheses and undermine the other?

A. When a prey insect is moved directly toward a beetle that has been chasing it, the beetle immediately stops and runs away without its usual intermittent stopping.

B. In pursing a swerving insect, a beetle alters its course while running and its pauses become more frequent as the chase progresses.

C. In pursing a moving insect, a beetle usually responds immediately to changes in the insect's direction, and it pauses equally frequently whether the chase is up or down an incline.

D. If, when a beetle pauses, it has not gained on the insect it is pausing, the beetle generally ends its pursuit.

E. The faster a beetle pursues an insect fleeing directly away from it, the more frequently the beetle stops.

OG解释：

Situation: Two hypotheses are offered to explain the sudden stop that tiger beetles make while pursuing their prey1) they cannot maintain the rapid pace and must rest, and (2) they run too quickly to process visual information and so temporarily go blind.

Reasoning: What point would strengthen one of the two hypotheses and weaken the other? Consider the information provided in each answer choice, remembering that information that supports one hypothesis must necessarily detract from the other. Any information that is not about pursuit or that affects the two hypotheses equally may be dismissed from consideration. If the frequency of stopping increases when the beetle follows a swerving insect and must constantly change its course, then the second hypothesis is strengthened; the beetle's pauses increases as the variety of visual information that it needs to deal with increases.

A. The hypotheses concern ongoing pursuit; since this information is not about the beetle's continuing pursuit of prey, it neither strengthens nor weakens either hypothesis.

B. Correct. This statement provides information that strengthens the second hypothesis: the swerving pursuit and the resulting continued course adjustment appear to be forcing the beetle to stop with increasing frequency to sort out the erratic visual information.

C. In this experiment, since neither vision nor tiredness appears to be problematic, the beetle could be stopping for either reason; this information neither strengthens nor weakens either hypothesis.

D. This information is irrelevant since both the hypotheses are about mid-pursuit behaviors.

E. The correlation of frequency of stops with speed affects both hypotheses equally; the pauses could be equally due to an inability to maintain the pace or due to a need to process the visual information.

这里A、D肯定是无关选项，E看了解释算是懂了。

C我做题的时候排除了，可是看了解释还是有点疑惑。我想问解释里说的vision和tiredness分别是怎么排除的。respond quickly to changes in direction和pauses equally frequently 分别起什么作用？

另外，问题最多的就是B，不知道最后那个its pauses become more frequent as the chase progresses为了说明什么，我就是因为这句话把这个排除了的。按理说应该和追insects fleeing directly away时候的pause比更多。同一次追捕中暂停越来越多是为了什么？这不是更倾向于累了所以要休息的理论？

有两个假设

1.peace不够，停下休息

2.大脑无法及时处理快速的变化，就blind了，然后停下了

选一个选项，支持一个，反对另一个

B说在追逐一个突然转向的昆虫的时候，甲虫也会改变它的方向，同时其追踪过程里，它pause的次数增加了。

B在突然转向的追踪过程里，这个甲虫pause次数增加了，可见能支持选项2，停下来处理信息。从而反对了1，不是因为体力的问题。

rapidly changing 和 突然转向是相对应的

。。还是不大明白。。

“B说在追逐一个突然转向的昆虫的时候，甲虫也会改变它的方向，同时其追踪过程里，它pause的次数增加了。”

还是不明白pause次数为什么增加，难道昆虫转向次数在增加？但是没有相关条件啊

可是我觉得在跑的过程中，随着时间推移，越来越累，需要休息，好像也说的通。。

还是说，这个算我自己的联想了？

rapidly changing 和 突然转向是相对应的

虫子的变向和文章中对于假设2的rapidly changing，是对应的，因此，虫子rapidly changing，结果是pause次数增加，刚好满足假设2的条件。加强了2

恩、、好吧，基本被说服啦。

不过老实说，我还是觉得B要是说pause more要比pause more frequently好。不管了，细节不追究啦。

谢谢gonghao版主和kallyliMM热情解答

我想估计我是打搅大家了,把一道老题翻出来.希望大家能够帮助一下刚上路的新手,这道题目虽然我作对了,但是对我打击太大了,因为他对我的逻辑体系提出了挑战,我毕业后还要去consulting 混啊...

因为我刚刚开始做OG11, 政策就是把每一道题的每一个选项和解释彻底弄清楚, 哪怕我作对了, 也耐下心来把所有有用没用的解释都看过去, 这样以后我才知道哪些是有用的(比如阅读中没办法坚决排除的选项的解释),哪些是没用的(比如明显是无关选项的相关解释就可以不看).一定要尽快的使自己的思路适应GMAC的, 这样后面可能就能够适应GMAT的考试. 我OG只打算做一次,最多把错题再作一次,因为我觉得有印象的题目多做意义不大.

这道题我答案是作对了,但是看了解释发现我是撞对了,思路完全和解释相反!(还好我对的题目也看答案)我有几个疑问, 看了上面的解释仍然没有办法解决,所以很担心自己的思路是不是有问题,自己的逻辑是不是有缺陷, 因为我完全反对答案的解释,甚至产生了OG解释编写者不不是理解错题目的意思(完了,我觉得我这个想法很可怕,对我以后复习都有影响):

1.解释说Any information that is not about pursuit or that affects the two hypotheses equally may be dismissed from consideration.我就强烈不觉得hypothesis是about pursuit的,我觉得它是一个关于甲虫体力和视觉处理的关于能力的问题,而不是关于追捕的问题,文章排除D时就说This information is irrelevant since both the hypotheses are about mid-pursuit behaviors., 但是我觉得D完全就是与hypothesis的具体内容无关,而不是与pursuit无关,所以才被排除.

A也一样! 我排除是因为它两个hypothesis都反对.A的意思应该是prey insect突然再being chased的过程回过头来move directly toward the beetle(我不知道有没有理解错),估计beetle很郁闷,不知道是不是很强悍的敌人,所以马上逃走. Beetle immediately stop说明了它再飞行中能够看到东西,反对假设2(假设2指视觉处理不行, 下同), 逃命的时候能够without intermittent stop说明它再特定情况下(逃命时)没有体力问题,所以反对假设1(指体力不行,下同). beetle在一般的pursuit中的停顿有可能是其他原因 

2. B选项问题最为严重, beetle alter its course while running,就是说它在飞行中也能够看见,能够反应(试想飞行中blind怎么可能alter its course),反对假设2. 她become more frequent在一个及其重要的前提下:as the chase progresses, 突然转向的prey在视觉的处理方面如果不是后面越转向越快,信息处理量应该差不多(假设prey和甲虫距离不变), 除非as the chase progresses,两者距离减少,这样后面的信息处理量就会增加,因为同样的专项对于甲虫而言转向所带来的角度变化更大,说到这里你也觉得太变态了吧, 我觉得"除非"后面的想法GMAC不会考的,因为转了太多弯了,所以我觉得还是按照前面的信息处理量不变, 那么, 就是说它的增多的停顿次数不是因为视觉信息处理量增大,那就是因为飞到后来累了,支持假设1, 所以这道题正确! 但是我的解释和og解释完全相反, 完了...

3. C也是,我觉得respond  immediately就否认了假设2, up or down a incline不变否认了假设1, 因为如果试体力问题, 向上飞肯定会比较容易累. 解释也说了,neither vision nor tiredness appears to be problematic,我非常同意.但是后面竟然说,the beetle could be stopping for either reason; this information neither strengthens nor weakens either hypothesis.我觉得明显就是neither reason站不住脚, 为什么题目认为是无关项

4. 虽然我还只是一个刚刚入门的人,但是还是想提一个不知天高地厚的问题, 如果我的解释是有道理的话(这是一个非常重要的前提),OG上面的题目+答案和解释可不可能是分开不同的人写的?因为我强烈怀疑这道题目解释的人并没有很好的理解好题目的意思,或者这是从一篇论文改造过来的题目,理解题目的人是基于论文其他部分的,就是他是对的,但是写成题目时因为信息量的限制,表达不是非常清晰,误导了我们.

如果题目+答案和解释是同一个人写的,那我就真的要好好反省一下我的逻辑思维能力了.

BTW 我是读工科的,所以可能想太多了,但是我的性格就是打破砂锅那种...

怎么说呢，总体来说这是一道BT题，至今我还是对它持保留意见，也许我理解能力有限吧。PREP软件中有道同样题干的题目，改了一个选项，结果就选改的那个选项。如果特别想弄清楚这题，你可以拿PREP那题参考一下

http://forum.chasedream.com/dispbbs.asp?BoardID=24&replyID=1706128&id=180492&skin=0

好久没来回帖了，顺便再多罗嗦几句我的建议吧

1、我赞同你说逻辑阅读题目做对的做一遍就够了，不过语法绝对有做多遍的价值。因为你即使做对，也不可能一次把语法点完全想全。所以一定要多做多揣摩！

2、大部分GMAT逻辑题的逻辑还是常规的，一个逻辑感很好的人（例如理工科生~）不用想太多是可以做对的。所以大可不必因为少数一两道tough题就置疑自己的逻辑感。关于题目的解释，老实说我遇到过少数几题OG的解释明显不好不能让我信服，所以是可以辨证的对待的，但是还是要学着从GMAT通常分析问题的思路来分析，而且当然绝大部分解释都是正确的。那种实在不清楚的题，如果打破沙锅之后还是保留疑惑，也不用纠缠太久浪费时间。

前几天一直在外面，今年才收到kathy8446的短信。

真的非常感谢kathy8446的细心指导！

其实这道题我仍然无法被解释说服，Prep那道题目我甚至觉得答案有问题，我觉得真确选项说beetle每次停顿的时间一样，但是在next stop后速度加快，不能肯定beetle视力或者体力有问题，反而给人感觉两个都没有问题。

关于这道题目考察能力还是方面，我的主要意思是他的确提出一个这样的pursuit中的停顿现象，但是后面cannot maintain和are unable to adequately process都是能力的缺陷导致他的这个习惯，我感觉beetle停顿是因为自身的某种能力不足，所以只要能够在任何地方（不一定在pursuit中）证明他有或者没有这些能力，就可以肯定或者否定某个假说。

其实随着我做OG，我会发现有些地方的解释他不一定完全正确或者合理……可能是每个人的思路不一样吧，我逻辑一般正确率都比较高，但是如果有错题的话经常出现不能够被答案完全说服的现象：）

我现在做OG都会把一切我觉得能够学到东西的信息记下来，比如某个SC的idiomatic expression, 作逻辑时先看问什么在读答案，RC中某个理解的缺陷，所以我希望以后只要能看笔记就行，不知道到时能否行得通……