og12 cr94 求助牛人啊

alex1206

Studies in restaurants show that the tips left by customers who pay their bill in cash tend to be larger when the bill is presented on a tray that bears a credit-card logo. Consumer psychologists hypothesize that simply seeing a credit-card logo makes many credit-card holders willing to spend more because it reminds them that their spending power exceeds the cash they have immediately available.

Which of the following, if true, most strongly supports the psychologists' interpretation of the studies?
(A) The effect noted in the studies is not limited to patrons who have credit cards.
(B) Patrons who are under financial pressure from their credit-card obligations tend to tip less when presented with a restaurant bill on a tray with a credit-card logo than when the tray has no logo.
(C) In virtually all of the cases in the studies, the patrons who paid bills in cash did not possess credit cards.
(D) In general, restaurant patrons who pay their bills in cash leave larger tips than do those who pay by credit card.
(E) The percentage of restaurant bills paid with a given brand of credit card increases when that credit card's logo is displayed on the tray with which the bill is presented.
请问怎样用XDF的方法解释这道题啊？原文据说应该是BA型，用否A推出否B即可，但不了解具体的推导方法啊，求解释！！！

xn8510

原文的假设是：盘中的信用卡标志使得信用卡持有者愿意多付钱，原因是该标志提醒了他们，他们的购买力超过了现金的购买力（比如，信用卡可以透支等等）

这个假设是因果关系，我们设结果为B，即B=“盘中的信用卡标志使得信用卡持有者愿意多付钱”，原因为A，即A=“该标志提醒了他们，他们的购买力超过了现金的购买力（比如，信用卡可以透支等等）”，那么，逻辑关系便是：A推出B

原命题成立，那么，其逆否命题也一定成立。否A=“信用卡标志提醒持有者，他们的购买力不足”，否B=“信用卡持有者不愿意多付钱”，原文中只有选项B是逆否命题：“Patrons who are under financial pressure from their credit-card obligations ”相当于否A（信用卡的还款压力使得持有者认为自己的购买力不足），“tend to tip less when presented with a restaurant bill on a tray with a credit-card logo than when the tray has no logo.”相当于否B（信用卡持有者不愿意多付钱），由此，B选项成立，起到了support的作用。。。

alex1206

多谢多谢啊！

娜么爱你之亮亮

不明白啊

按你的解释，B选项是否A推出否B。


这怎么是逆否呢？


逆否应该是否B推出否A吧？

呓语

看了这个一下子就明白了~感谢~

i5land

受教～～

ponta

同意三楼，而且不大明白c为啥不对碍，求nn解答~

呓语

C是无关选项啊。原文说的是 因为看到盘子上面的信用卡LOGO来提醒顾客有更大的支付能力（透支啊之类的），明显讨论的是有信用卡的人。没用信用卡的看不看到都没有任何关系。

怪兽党

求问OG解释中“ this explanation would not be valid even if those people who are not reminded of their own excess purchasing power- if in fact they have any such power-when they see such a logo nonetheless tip more in such trays” 是什么意思啊

jofre

OG解释B选项正确的逻辑过程：
1）The conclusion ofthe argument: 看见logo后给更多小费的原因为logo提醒人们有更多消费能力，即“logo提醒人有钱”是“给多小费”的原因；
2）B选项，没钱人看见logo（即logo没提醒人有钱）不会多给小费；B否，logo没提醒人有钱，也会多给小费；
3）若B否成立，则conclusion错误：“logo提醒人有钱”不是“多给小费”的（唯一）原因，有其他因素导致“多给小费”，从而weaken the conclusion；
4）因此B选项strengthen the conclusion