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 creditcard logo. Consumer psychologists hypothesize that simply seeing a credit-card logo makes many creditcard 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?
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!!!
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。。。
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