OG 11th, Diagnostic Test #25

mko

25. Tiger beetles are such fast runners that they can capture virtualy any nonflying insect.  However, when running toward an insect, a tiger beetle will intermittently stop and then, a moment later, resume its attack.  erhaps the beetles cannot maintain their pace and must pause for 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 artificially moved 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 immidiately stops and runs away without its usual intermittent stopping.
B. In pursuing a swerving insect, a beetle alters its course while running and its pauses become more frequent as the chase progresses.
C. In pursuing 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 beele pauses, it has not gained on the insect it is pursuing, the beetle generally ends its pursuit.
E. The faster a beetle pursues and insect fleeing directly away from it, the more frequently the beetle stops.

The answer is B
OG says: 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 theat 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 increase as the variety of visual information that it needs to deal with increases.

B Correct.  This statement provides information that stengthens the 2nd hypothesis: the swerving pursuit and the resulting continual course adjustments appear to be forcing the beetle to stop with increasing frequency to sort out the erratic visual information.

我选了C,因为当时做题时就比较急,觉得不是B就是C,现在仔细看以后觉得B比C更合适,但是我想问对于题干的问题,如何看待这个 support one of the two hypotheses and undermine the other,B的解释没有说明怎么undermine另一个假设,虽然B更倾向于适合第二个假设,但是我觉得并不能就undermine第一个,怎么看待这个undermine的意思呢? 多谢 (题是手敲的,有错误请谅解)

seasnow

这道题好难啊。

看答案之后我自己想出来的一个理解，不知道是否合适，请大家讨论：

B中提到了more frequent，我想这个是undermine了第一个假设。因为第一个假设说的是因为跟不上步伐，所以过一阵要歇一会；然而题中并没有提到速度越来越快，就有了停的次数越来越多，这显然与第一种假设矛盾，说明必然有其他的原因导致停的次数越来越多，所以就构成了一个他因削弱。

这样解释行得通吗？

mko

行的通,谢谢.但是感觉undermine的程度和support的程度不相同.

bluevironika

我觉得是这样的：

one：Perhaps the beetles cannot maintain their pace and must pause for moment's rest（体力不支）

the other：tiger beetles are unable to adequately process the resulting rapidly changing visual information and so quickly go blind and stop.（视力不支）

og 要求要找出其中一个的支持项，一个的反对项。

a，无关。因为tiger beetles跑开了。

b，tiger beatles追逐中随着猎物的路线改变而改变，并且越来越频繁的休息。（所以说，他的视力没有问题，是体力不支了）

c，他随着猎物的路线改变，而且休息的频率很平均。（视力没有问题，赞成了一项，但是没有对另外的一个体力不支的情况作进一步的说明）

d，无关。与a一样。

e，跑的越快，停的越多。（赞成是其中一项，另外一项也没有说）

请指教！

seasnow

好像说反了吧：

OG says: 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 theat 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（视力不行） is strengthened; the beetle's pauses increase as the variety of visual information that it needs to deal with increases.

跟不上pace不能译为体力不支吧。

To be discussed...

mko

谢谢,我是这么认为的:
B. In pursuing a swerving insect, a beetle alters its course while
running and its pauses become more frequent as the chase progresses.
B似乎是在说beatle的频繁停顿是因为视力不行,因为路线老改变,所以它晕的次数就多了,停顿的次数也增加了,不得不停顿来确定追的东西到底在哪.但是并没有明显的证据来削弱不是体力不支.可能seasnow说的,速度并没有越来越快,而停的越来越频繁,所以肯定不是体力不支造成的停顿. 即使是这样解释,也觉得undermine的程度不够,但是看看其他似乎这个选项最靠近了.或者是还有更好的解释?请讨论,谢谢.
C.
In pursuing 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.
C现在比较明确了,immediately说明视力没问题,那么如果说明体力有问题,就成了.但是下一句却说pauses equally frequently up and dwon hill说明体力也没问题,所以既不是视力也不是体力问题,同时削弱,所以错.

bluevironika

不好意思，犯错误了，我没有看og的详细说明，这里更正下，sorry。谢谢seasnow妹妹。

我的补充理解是：

1：Perhaps the beetles cannot maintain their pace and must pause for moment's rest（体力不支）

2：tiger beetles are unable to adequately process the resulting rapidly changing visual information and so quickly go blind and stop.（视力不支）

a，无关。因为tiger beetles跑开了。

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

在对一个swerving动物的追逐中，beetle边跑边改变了他的路线，在追逐过程中，他的停顿变得越来越频繁 。1里面说，他的停顿是为了休息，就是体力不支了；如果这一项被支持的话，那么他的停顿也就不是为了视力缘故，所以，2的说法就被消弱了。同样的，如果他的停顿是为了适应swerving 的动物，就不是为了体力不支，1的说法就被消弱了。

c，他随着猎物的路线改变，而且休息的频率很平均。（视力没有问题，赞成了一项，但是没有对另外的一个体力不支的情况作进一步的说明）

d，无关。与a一样。

e，跑的越快，动物逃开越远，停的越多。（赞成其中的一项，但是加进了一个新的因素， insect fleeing directly away from it,就是说动物的直接逃逸也影响了他的停顿，那就不能单纯的考虑题目给我们的两个停顿原因了。）

关于我对b的解释，我觉得要回到问题上来

which of the following, if discovered in experiments using artificially moved insects, would support one of the two hypotheses and undermine the other? 题目要我们支持其中一项，消弱另外的一项，并没有明确的说要我们消弱哪一项.从语法的角度，one...the other分别就是指的两个当中的一个..另外一个...，用来作分别的说明；在gmat的逻辑prefer里面，也说了，题目里面说什么就是什么，不要做过多的发挥，mko觉得b的消弱不够，我觉得是这样的，这里题目要求我们就两个issure找寻答案，就为我们假定了非此即彼的范围。所以，我对答案b的理解，如上所示。而其他的选项，说明的对象或超出了这两个issure（e），或作了无关的说明（a，d），或说明不充分（c），所以b 是正确的答案。

不当之处，请大家多多指教

[此贴子已经被作者于2006-1-4 21:24:58编辑过]

seasnow

嗯，再看一遍，觉得满有道理的。

就是说，题目已经明确告诉我们两个观点是trade－off的，一个成立另一个就被削弱。

所以考虑的时候只需要看一个观点，然后当成纯粹支持题或者纯粹削弱题来做就好了。

当然，还有一个难度，就是如果当成他因削弱，这个他因必须是alternative的那个观点，所以可能当成支持题做会好一点。

Fibonecei

我对这题的理解也很不确定.

但是我觉得og上的解释说b是赞成"视力不支",这显然不如b赞成"体力不支"来得显然.因为时间飞得越长,beatle就会越累,这是肯定的。但是飞的时间长,并不意味着视觉图象改变快.既然没有说速度是不是变快了,那就不能确定视觉图象的变化是不是加剧了.但是时间长了,体力是肯定不支的.

我觉得b是两个都赞成,而不是赞成一个削弱另一个.那些所谓的削弱似乎是我们自己给他加上去的.

而c是两个都削弱.

boochxu

   OG 11th, Diagnostic Test #25, 这个Diagnostic Test是什么，从来没听过啊？