有几题怎么想都不明白，请教大仙~~~~~~~

tyzgmat · 发表于 2011-4-25 22:49:09

og_11_096
Commentator: The theory of trade retaliation states that countries closed out of any of another country’s markets should close some of their own markets to the other country in order to pressure the other country to reopen its markets. If every country acted according to this theory, no country would trade with any other.

The commentator’s argument relies on which of the following assumptions?

(A)   No country actually acts according to the theory of trade retaliation.
(B)   No country should block any of its markets to foreign trade.
(C)   Trade disputes should be settled by international tribunal.
(D)   For any two countries, at least one has some market closed to the other.
(E)   Countries close their markets to foreigners to protect domestic producers.

og_11_v07/ og_10_048
A researcher discovered that people who have low levels of immune-system activity tend to score much lower on tests of mental health than do people with normal or high immune-system activity. The researcher concluded from this experiment that the immune system protects against mental illness as well as against physical disease.

The researcher’s conclusion depends on which of the following assumptions?

(A)   High immune-system activity protects against mental illness better than normal immune-system activity does.
(B)   Mental illness is similar to physical disease in its effects on body systems.
(C)

eople with high immune-system activity cannot develop mental illness.
(D) Mental illness does not cause people’s immune-system activity to decrease.
(E)

sychological treatment of mental illness is not as effective as is medical treatment.

15og_11_112/ og_10_087
In tests for pironoma, a serious disease, a false positive result indicates that people have pironoma when, in fact, they do not; a false negative result indicates that people do not have pironoma when, in fact, they do. To detect pironoma most accurately, physicians should use the laboratory test that has the lowest proportion of false positive results.

Which of the following, if true, gives the most support to the recommendation above?

(A)   The accepted treatment for pironoma does not have damaging side effects.
(B)   The laboratory test that has the lowest proportion of false positive results causes the same minor side effects as do the other laboratory tests used to detect pironoma.
(C)   In treating pironoma patients, it is essential to begin treatment as early as possible, since even a week of delay can result in loss of life.
(D)   The proportion of inconclusive test results is equal for all laboratory tests used to detect pironoma.
(E)   All laboratory tests to detect pironoma have the same proportion of false negative results.

虽然都是有解答的，可是答案看得我蛋疼都得不出结果，有高人指点一下吗

joananna · 发表于 2011-4-25 23:16:19

答案是什么啊？DDB么？

tyzgmat · 发表于 2011-4-26 23:02:02

答案是 DDE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
有人教一下吗？？？？？？？？？？？？？？？？？？？

sdcar2010 · 发表于 2011-4-27 06:36:13

096

Necessary assumption. Use negation.

(D) For any two countries, at least one has some market closed to the other.

If you negate choice D, then any two countries would have no market closed to the other. Ask yourself what would happen? Nothing! The trade goes on. Thus, the argument falls apart. Therefore, D is a necessary assumption that the argument relies on.

tyzgmat · 发表于 2011-5-2 23:08:21

明白一提啦
还有两题哪个好心人帮忙解答一下啊！

nileshu · 发表于 2011-5-2 23:39:00

最后一题可能需要点统计学背静知识了吧。为了追求I型错误最低，也就是“拒真”错误最低，II型错误（“取伪”错误）就会相应提高。二者有此消彼长的关系。所以到最后，所有实验室的取伪错误都一样了。

tyzgmat · 发表于 2011-5-3 16:49:24

LS，谢谢啊。
可是你解释的我一头雾水，能整个简单得不？
各位NN帮下忙啊

kikisunflower · 发表于 2011-5-3 17:21:10

og_11_v07/ og_10_048：
属于常见题型，通过一个实验发现两个现象之间有联系，即“low immune system“和“mental illness”这两个现象是有关的。然后作者就推论，说“low immune system”导致了“mental illness”。

但是事实上，作者没有理由这么说的，因为既然是两个平行出现的现象，怎么知道谁是因谁是果。所以作者要得出结论，必须先排除“mental illness”导致“low immune system”的可能。

写arguement的时候也常见这类错误。即coorelation mistaken for causation以及confuse the cause and effect

kikisunflower · 发表于 2011-5-3 17:27:25

15og_11_112/ og_10_087:
结论是医生想通过采用false positive最少的机器，来达到精确测量某个疾病的目的。

但是题目条件说了，这些机器不仅会出现false positve的情况，也会出现false negative的情况，怎么确保医生用的方法就能达到精确测量的目的哇？

那就是false negative的情况是固定的，没发改变了，对所有机器都一样。
如果有这个前提存在，那么医生只选择false positive发生最少的机器就可以达到精确测量的目的了。

有几题怎么想都不明白，请教大仙~~~~~~~

所属分类: GMAT考试

正在浏览此版块的会员 ()