Could it be that humans are not quite as gullible as advertised?

    For a couple of decades now, social psychologists and behavioral economists have been amusing themselves manipulating consumers into doing odd things. They've delighted in debunking the notion of homo economicus, that theoretical creature who rationally seeks maximum economic utility.

    Old-fashioned cost-conscious consumers would react to a price increase by lowering demand for the product, but we sometimes do just the opposite. We want to buy more of it because we assume it must be a better product - and we're so thoroughly fooled that our bodies even respond differently to it.

    If you give people a placebo and tell them it's a painkiller costing $2.50, they can withstand painful shocks better than if they're told the pill costs a dime. Give them an energy drink at a discount price, and they'll perform worse on subsequent tests than if they pay full price. If you tell them the wine they're tasting costs $90 a bottle, then the reward centers of their brains will light up more than if you tell them it's a $10 bottle.

    But suppose, instead of scanning people's brains as they're sipping wine in a laboratory, you tested them in a more realistic situation: a restaurant where they're spending their own money. That challenge was undertaken at an upscale restaurant in Tel Aviv by two behavioral economists, Ori Heffetz of Cornell and Moses Shayo of the Hebrew University of Jerusalem, who expected to be able to manipulate diners' choices by changing the prices on the menu.

    Unbeknownst to the diners or to their waiters, the economists monitored the choices of people who ordered from the prix fixe menu. The three-course meal cost included a choice of five entrees: shrimp gnocchi, pork shank, red mullet fillet, sausage or stuffed artichoke.

    Next to each of these entrees on the menu, in parentheses, was the cost of what it would cost to order that entree from the à la carte menu. These prices didn't affect the cost of the prix fixe meal, which was the equivalent of $30 no matter what the entree, but the researchers expected just the sight of the prices to make a difference. If the mullet were listed at $20 and the other entrees were $17, more people would presumably be enticed into ordering the seemingly more valuable fish.

    But after three months of testing various combinations of prices, the researchers found they couldn't sway the customers. Putting a higher price on the shrimp or any other entree didn't make people more likely to order it.

    This same stubbornly independent streak was manifest in another food experiment by the same researchers. This time they let people sample two kinds of candies - peanut butter bars and caramels - and varied the sticker prices for each one.

    Superficially, the manipulation seemed to work, because people said they would be willing to pay more for a candy if it had a higher sticker price, but that was just in answer to a hypothetical question. When people were given a chance to pick a bag of candy to take home, they pretty much ignored the sticker prices and chose what they liked.

    Why weren't people duped into favoring the high-priced candies and entrees? Why did they follow their own tastes?

    "Maybe, sometimes, old-fashioned economics is just about right," Dr. Shayo says. "Maybe when it comes to food, people do have reasonably stable preferences. Some people like shrimp and some don't, even if it's worth a lot of money."

    The researchers don't deny that consumers can be swayed by variations in sticker prices in laboratory experiments. But they question how significant that factor is in real-world settings where prices can't be inflated so extremely, like the Tel Aviv restaurant. "Size is everything," Dr. Heffetz says. "Our findings remind us that knowing that 'A has a positive effect on B' is not enough. The effect may simply be too small to matter."

    The size-matters effect seemed to show up in a much less rigorous bit of research conducted at my TierneyLab blog with the help of Geoffrey Miller, an evolutionary psychologist at the University of New Mexico. In his new book, "Spent: Sex, Evolution and Consumer Behavior" （Viking）, he argues that humans often waste money because of the unconscious - and mistaken - belief that our costly stuff will signal our intelligence and sterling personality traits to potential mates and allies.

    As an exercise, Dr. Miller asked readers of the blog to list the 10 most expensive things they had ever bought, and then list the 10 purchases that had brought them the most happiness. More than 200 responded. As we expected, many people rued spending lots of money for stuff that hadn't brought them joy. Boats seemed to have particularly low utility in delivering happiness per dollar; many cars fit that category, too, and so did many expensive weddings.

    But we were struck by how much overlap there was between the most-expensive list and the most-happy list. People repeatedly included on both lists their homes, their college education, their vacation trips, their high-priced electronics （large-screen televisions, Blu-Ray player, audio equipment, computers） and certain models of cars （BMW 325, Audi A4, Jaguar, Subaru WRX, Toyota Prius, Honda Civic）.

    Indeed, the first trend that Dr. Miller identified was the match between the happiness and expense lists. Some of this may have been because of postpurchase rationalization, but a lot of buyers seemed to be suffering anything but remorse. As one reader, Janet Hubbs, put it:

    "The three things （not necessities） I have spent the most money on in the past ten years are: my cottage at Cape Cod, my Lexus, and my Rolex - and I LOVE all three, in the order of their cost. And I don't care what that says about me."

    花多少錢能買到快樂呢？

    也許人們并不是那么容易被廣告騙到？

    過去幾十年來，社會心理學家和行為經濟學家們一直為能操控消費者作出種種蠢事而自鳴得意。他們為能證明制度經濟學中理性經濟人尋求經濟效用最大化是錯誤的而沾沾自喜。

    如果物價上升了，那么傳統的以價格為重的消費者會減小自己對該商品的需求。但是，受"一等價錢一等貨"的影響，有時我們反而會買的更多。我們不僅腦袋被騙了，連身體反應都會因此改變。

    比如，如果你給一個人一劑安慰劑，但卻跟他說這是一片值2.5美元的止疼片，那他吃了以后肯定覺得身體也不是那么疼了。但如果你告訴他，這只值10美分，他又會覺得劇痛難耐了。又比如，人們按全價買的運動飲料會讓他們表現神勇，但如果是打折買的，他們的表現就會大打折扣。再比如，人們飲酒時，如果你告訴他們這酒價值90美元，那他們肯定會對這就贊譽有加，可如果你告訴他們這只值10美元呢？

    除了在實驗室里掃描飲酒人的腦部反應外，設想一下，如果我們在一個更真實的場景里測試他們，比如在餐館里自掏腰包就餐時情況又會是怎樣的呢？來自康奈爾的Ori Heffetz和耶路撒冷希伯萊大學的Moses Shayo兩位行為經濟學家在特拉維夫高級餐廳進行了一項實驗，他們希望能通過改變菜單價格來操控食客們的選擇。

    在對食客和侍者的情況都不了解的條件下，兩位經濟學家觀察記錄了人們點套餐時的選擇。套餐有三道菜，其中主食有五種可供選擇：蝦球、豬腿肉、紅鯔魚排、香腸以及洋薊菜泥。為了讓價格有個對比，研究者在五種菜旁的括號里標出了他們單點時的單價。而這些單價是不會影響套餐的價格的，因為不管點什么，套餐都是30美元。根據研究者的推測，如果鯔魚排標價20美元，而其他菜標價17美元，那么人們更愿意選擇相對較貴的魚排。

    但是三個月過去了，研究者們發現：不管怎么改變價格組合，他們都無法左右食客們的選擇。人們不會因為蝦球或其他某一道菜的價格高就點它。

    兩位經濟學家又進行一次食物測試，可是，這次的結果還是和他們的預期南轅北轍。在這次實驗中，他們讓人們在飴糖和花生黃油棒棒糖兩種價格不一的糖中做出選擇。

    從表面上看，價格操控奏效了：實驗參與者稱，他們會買價格更高的糖。但是，這只是"紙上談兵"罷了。當研究者們要他們買一袋糖時，人們卻不顧價格而是按著自己的口味買了。

    人們為什么不受高價糖果和主菜的誘惑？為什么跟著自己的口味走呢？

    Shayo博士解釋道："有時候，也許傳統經濟學說的在理。人們對食物都有固定的偏好。就像有人喜歡蝦子；有人不喜歡，即使它很貴。"

    在實驗室條件下消費者是會受價格變化影響的。對此，研究人員非常肯定。但他們提出這樣一個疑問，即在象特拉維夫餐館一樣的現實世界里，物價是不可能亂漲的，那么價格對人的影響有多大呢？heffetz博士說："關鍵是大小。我們的實驗告訴我們光知道'甲對乙有正影響'是不夠的，因為這種影響可能微不足道。"

    筆者和杰弗里米勒進行了一個放寬條件的研究，其中也涉及了影響大小的問題。這個研究登在了在我的tierney實驗室博客中。杰弗里米勒是新墨西哥大學的一名進化心理學家，在他的新書《消費：性別、進化和消費者行為》中，他講到人們之所以花大價錢買東西是因為他們無意識地或錯誤地認為我們買的東西越貴，越能讓我們周圍的人感到我們的智力或者品格很高。

    米勒博士做了個小測試。他要我們博客的讀者列出自己曾買過的最貴的10樣東西還有最讓自己買后覺得快樂的10樣東西。有200多人參與了測試。正如我們所料，很多人覺得很后悔，他們花了很多錢卻沒得到快樂。以一美元計，船給人們帶來的快樂最少，很多汽車和奢華的婚禮也位列其中。

    但是，我們也驚訝的發現最貴消費清單中所列的東西很多都出現在最讓人快樂的消費清單中。人們在兩張清單中都寫上了房子、大學教育、假期旅行、昂貴的電子產品（大屏電視機、藍光播放器、音頻設備和電腦）以及一些名車（寶馬325、奧迪A4、積架、斯巴魯WRX、豐田prius、本田civic）

    確實，米勒博士發現的第一個趨勢就是：花大錢買的東西也會讓人覺得快樂。有些人能解釋為消費后合理化現象（人們在花了大量金錢、時間后努力說服自己它必須是值得的）.但更多的人花了錢后一點兒也不后悔。正如讀者珍妮特哈布斯這樣寫到：

    "在過去十年里，我在科德角的小屋、凌志車和勞力士是我買過的最貴的三件東西。盡管不是生活必需品還價格不菲，可是我愛死它們了。我才不管別人怎么說我呢！"