逻辑请教OG11－112题！！

Tima2009

逻辑题。OG 11－112题／

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, give the most support to the recommendation above?

A) the accepted treatment for pirononma does not have damaging side effect.

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.

正确答案是（E）  请NN给详细解释一下。 小女子不胜感激。

hughlv

A), B), C)都很容易可以被排除掉，因为是跟目标to detect pironoma most accurately没有关联。精确度的定义是正确的检测结果除以总检测样本数。正确样本数+false positive+false negative=总检测样本数。所以要提高精确度的方法就是尽量降低false positive+false negative的值。D)说明了这个和是一个常数，所以无法提高精确性，而E）则满足，因为false negative的比例不变，所以如果降低false positive的比例则整体精度会提高。

说白了就是一个用复杂英语和例子描述的小学数学题了。

另外善意提醒一下，lz自称小女子但是头像可是个帅哥，大概个人信息里没填对吧。

Tima2009

我用的是别人的账户。谢谢楼上NN的解释，非常全面，谢谢啦！

snake37

没那么复杂啦，其实这种题还是不少的：
就是说这里有一件事情有两个缺点，我们要集中力量解决其中的一个，问如何加强这一决定。

加强的方法很简单：那就是另一个缺点我们无能为力！

这里就是说false negative results无法通过实验来降低，那只好尽可能降低false pisitive results啦