返回列表 发帖

狒狒逻辑详解94

请问答案是否为 A? 我对以下五个答案选项的理解不太清晰. 下面的思路对吗?谢~

94. When 100 people who have not used cocaine are tested for cocaine use, on average only 5 will test positive. By contrast, of every 100 people who have used cocaine 99 will test positive. Thus, when a randomly chosen group of people is tested for cocaine use, the vast people is tested for cocaine use, the vast majority of those who test positive will be people who have used cocaine.

A reasoning error in the argument is that the argument

A. attempts to infer a value judgment from purely factual premises

B. attributes to every member of the population the properties of the average member of the population

C. fails to take into account what proportion of the population have used cocaine

D. ignores the fact that some cocaine users do not test positive

E. advocates testing people for cocaine use when there is no reason to suspect that they have used cocaine

未服用可卡因的100人中,95阴性5 阳性,显阴性的比例为95%,显阳性的比例为5%

服用可卡因的100人中,1阴性99 阳性,显阳性的比例比例为99%,显阴性的比例为1%

随机100人中,显阳性的总人数= 5% x未服用的人+ 99% x服用的人 (总人数决定是否为vast majority ),显阳性的比例= 显阳性的总人数/ (未服用的人数+ 服用的人数)

收藏 分享

我记得是C

when a randomly chosen group of people is tested

如果被选的人 大部分是people who have not used cocaine

则 test positive 的不见得大部分都是used cocaine的

TOP

返回列表

站长推荐 关闭


美国top10 MBA VIP申请服务

自2003年开始提供 MBA 申请服务以来,保持着90% 以上的成功率,其中Top10 MBA服务成功率更是高达95%


查看