似乎有點不對勁

經濟學人

The psychology of discounting
打折心理

Something doesn’t add up
似乎有點不對勁

How marketers can take advantage of consumers’ innumeracy
營銷人員如何利用數學盲消費者

WHEN retailers want to entice customers to buy a particular product, they typically offer it at a discount. According to a new study to be published in the Journal of Marketing, they are missing a trick.
零售商若想慫恿顧客購買某種產品，往往會打個折。一項即將發表在《市場營消雜志》（the Journal of Marketing）上的新研究表明，零售商們忽略了一個竅門。

A team of researchers, led by Akshay Rao of the University of Minnesota’s Carlson School of Management, looked at consumers’ attitudes to discounting. Shoppers, they found, much prefer getting something extra free to getting something cheaper. The main reason is that most people are useless at fractions.

由明尼蘇達州大學卡爾森管理學院（University of Minnesota’s Carlson School of Management）的阿克什•勞（Akshay Rao）帶領的一個研究團隊就消費者對打折的態度進行了研究。他們發現，與較低的價格相比，購物者更喜歡獲取免費贈品。主要是因為一涉及分數計算，多數人的腦子都轉不過來。

Consumers often struggle to realise, for example, that a 50% increase in quantity is the same as a 33% discount in price. They overwhelmingly assume the former is better value. In an experiment, the researchers sold 73% more hand lotion when it was offered in a bonus pack than when it carried an equivalent discount (even after all other effects, such as a desire to stockpile, were controlled for).

例如，消費者往往很難意識到加量50%與打六七折其實是等價的。他們大多認為前者更劃算。在一項實驗中，研究人員以優惠裝出售護手霜比打同等折扣多賣了73%（即使在其他影響，如顧客想多買一點，都被排除在外時也是如此）。

This numerical blind spot remains even when the deal clearly favours the discounted product. In another experiment, this time on his undergraduates, Mr Rao offered two deals on loose coffee beans: 33% extra free or 33% off the price. The discount is by far the better proposition, but the supposedly clever students viewed them as equivalent.

即使很明顯是打折比較劃算，消費者的數學盲點依然存在。在另一項實驗中，這次實驗對像是阿克什•勞的本科生，阿克什•勞給出了兩種購買散裝咖啡豆的方法：免費多送33%和價格降低33%。這個折扣比免費贈送劃算得多，但那些看起來很聰明的學生卻認為兩者一樣。

Studies have shown other ways in which retailers can exploit consumers’ innumeracy. One is to befuddle them with double discounting. People are more likely to see a bargain in a product that has been reduced by 20%, and then by an additional 25%, than one which has been subject to an equivalent, one-off, 40% reduction.

這些研究表明零售商還有其他方式可以利用消費者的數學盲點。其中一種就是用折上折來迷惑他們。人們往往會覺得，先打八折再打七五折比一次性只打六折更劃算，其實兩者根本一樣。

Marketing types can draw lessons beyond just pricing, says Mr Rao. When advertising a new car’s efficiency, for example, it is more convincing to talk about the number of extra miles per gallon it does, rather than the equivalent percentage fall in fuel consumption.

阿克什•勞說，除了產品定價，人們還可以從這些研究中學到關於市場營銷的其他技巧。例如，為一款新車的性能做廣告，宣傳每加侖的油能多跑多少英裡比實質上能省多少油更有說服力。

There may be lessons for regulators too. Even well-educated shoppers are easily foxed. Sending everyone back to school for maths refresher-courses seems out of the question. But more prominently displayed unit prices in shops and advertisements would be a great help.

監管部門也可能從中學到東西。即使是受過良好教育的購物者也很容易被忽悠。讓大家重返校園進修數學似乎不大可能，不過在商店和廣告中更明顯地標出產品單價將會有莫大的幫助。