People who have spent a lot of time in contact with animals often develop animal-induced allergies, some of them quite serious. In a survey of current employees in major zoos, about 30 percent had animal-induced allergies. Based on this sample, experts conclude that among members of the general population who have spent a similarly large amount of time in close contact with animals, the percentage with animal-induced allergies is not 30 percent but substantially more.
Which of the following, if true, provides the strongest grounds for the experts' conclusion?
A zoo employee who develops a serious animal-induced allergy is very likely to switch to some other occupation.
A zoo employee is more likely than a person in the general population to keep one or more animal pets at home
The percentage of the general population whose level of exposure to animals matches that of a zoo employee is quite small.
Exposure to domestic pets is, on the whole, less likely to cause animal-induced allergy than exposure to many of the animals kept in zoos.
Zoo employees seldom wear protective gear when they handle animals in their care.
情景:调查显示动物园雇员有30%概率被动物传染某种病。但这个例子中专家认为在和动物密切接触人中患病的概率要高于30%,问grounds。
答案预估:给的sample是30%,专家说要高于30%,那么依据应该是例子中的比例有所低估,找出能给出比例低估的选项即可。
A:得这种病的动物园雇员很可能换工作了。所以现在sample中其实少了一些得了重病换工作的人,所以这个比例是低估的。Correct。
B:动物园雇员比一般人更可能养一两只宠物,没有办法佐证。错误。
C:普通人中和动物接触程度类似动物园雇员的非常少,题目比较对象是接触程度=雇员的,质疑了题干的条件,错误。
D:和宠物接触与和动物园动物接触相比更不可能患病,那普通人患病比例应该低于30%,错误。
E:动物园雇员很少穿防护服,和比例被低估无关。错误。
这题出的权威吗, 总觉得题不对. 一般逻辑不是这种思路觉得
数据样本问题,有过敏的已经换工作了,说明样本中过敏比例本应该是要大于30%的
为啥不选E……
A 工作人员转职了——普通人过敏的比例增加——保留——B 工作人员更可能接触动物,削弱 C 普通人更不可能接触动物 削弱——D 接触家养动物更不可能过敏削弱——E工作人员很少穿防护服,说明工作人员过敏是因为不穿防护服 普通人情况没说
背景: 和动物接触很多的人容易患上动物引起的过敏症状。在一项调查中,主要动物园的员工中有30%患有前文提到的过敏。
结论:在这个数据基础上,专家推断在广大群众中接触动物时间比较多的人中,有过敏症状的人要比30%更多。
问grounds就是问为什么普通人患过敏的人要更多?
A 动物园工作人员患过敏之后,ta会转行。这说明现在动物园调查的数据是偏少的,已经有一部分患病的工作人员变成了general public,如果不转行,这个数据会比30%要大。再类比,得出general public的过敏比例要大于30%。
类比型的推论,需要指出两者的区别就可以削弱类比关系