问两道manhattan FoV上的逻辑习题

udsifhi

Researchers have noted that panda bears that have given birth to live young live longer in the wild. Therefore, these researchers have concluded that giving birth to live young increases a panda's lifespan.
The argument makes which of the following assumptions?
(A) Pandas that have given birth to live young will not be killed by predators.
(B) Since male pandas cannot give birth, female pandas live longer than male pandas.
(C) Pandas that are already likely to live longer are also more likely to give birth to live young.
(D) Female pandas are not likely to die while giving birth.
(E) Pandas that have given birth to multiple live young are likely to live even longer than pandas that have given birth to only a single live offspring.
（答案C）
这道题问的是假设，但是我觉得C是削弱啊，如果C对，不就证明argument里的因果关系不对吗？

Over the past three decades, the number of hospital beds available for inpatient psychiatric treatment in the United States has declined from 4 per 1,000 population to 1.3 per 1,000 population. Over the same period in Japan, beds increased from 1 per 1,000 population to 2.9 per 1,000 population. Also during this period, annual mortality rates for persons with mental disorders have risen substantially in the United States, while declining in Japan.
To support a conclusion that the reduction in hospital beds is principally responsible for the increase in mortality in the United States, it would be important to establish which of the following?
(A) Whether the number hospital beds available for inpatient psychiatric treatment has risen or declined in countries demographically similar to the United States.
(B) The number of hospital beds available for inpatient psychiatric treatment in the United States prior to the three-decade period under discussion.
(C) Whether other factors, such as a decreased occurrence of mental disorders, may have led to the decline in mortality in Japan.
(D) Whether mental health care is more comprehensive in the United States or in Japan.
(E) Whether other factors in the United States may have led to increased mortality for persons with mental disorders.
答案（E）
C为什么不对？

udsifhi

CC_Vera

第一题Manhattan 论坛上说了， C的答案错了，少了一个“not”。 所以，C 应该是：Pandas that are already likely to live longer are not also more likely to give birth to live young. 所以答案eliminates the possibility that the stated relationship is reversal.


第二题：这题的结论是：the reduction in hospital beds is principally responsible for the increase in mortality in the United States.
这题correlation and causation:
1. 美国 bed available per 1000 population 减少，同时，死亡率mortality增加。
2. 日本 bed available per 1000 population 增加，同时，死亡率mortality减少。
结论：reduction in bed  increase in mortality in USA.
C: 在日本是否其他因素导致死亡率增高？-- 无关。是，或不是。对USA没有任何影响。
E: 在美国是否其他因素导致死亡率增高？是，那么conclusion就打了折扣了。不是，那么这个结论有点被strengthen的感觉了。

udsifhi

CC_Vera 发表于 2015-2-16 12:33
第一题Manhattan 论坛上说了， C的答案错了，少了一个“not”。 所以，C 应该是：Pandas that are already  ...

谢谢