????斯坦福大學(xué)MBA畢業(yè)生、OwnerListens公司的聯(lián)合創(chuàng)始人阿迪?比坦告訴我，目前企業(yè)主要采取了兩種類型的策略：“白帽”和“黑帽”。“白帽”戰(zhàn)略一般會(huì)先找到最滿意的顧客，然后鼓勵(lì)他們?cè)跓衢T網(wǎng)站上撰寫評(píng)價(jià)。“黑帽”戰(zhàn)略即給競(jìng)爭(zhēng)對(duì)手甚至是潛在的競(jìng)爭(zhēng)對(duì)手寫差評(píng)、扣帽子。比如有人在Yelp上只給了芝加哥名廚格拉罕姆?艾略特的三明治和冰淇淋店1星評(píng)價(jià)，那人還說，當(dāng)他走到那家店時(shí)發(fā)現(xiàn)它關(guān)門了，結(jié)果毀掉了“他原本愜意的散步心情”。但事實(shí)上，當(dāng)時(shí)根本還沒有到那家店的營(yíng)業(yè)時(shí)間。艾略特舉這個(gè)例子來(lái)說明差評(píng)究竟可以沒有下限到什么程度。他對(duì)Yelp的評(píng)價(jià)用詞基本上不適合發(fā)表。

????除了虛假和不實(shí)評(píng)分以外，口碑經(jīng)濟(jì)還有其它更多的問題。為了吸引顧客的評(píng)價(jià)，企業(yè)有時(shí)會(huì)采取沒有任何用處，甚至有害的方法來(lái)“刷好評(píng)”。

????再次以教師的評(píng)分為例。大家都知道這樣一個(gè)潛規(guī)則：教師要想獲得更高評(píng)分，其中一種方法，便是給有評(píng)分權(quán)的學(xué)生更高的分?jǐn)?shù)。正是由于“要好評(píng)”心理的作祟，這種現(xiàn)象已經(jīng)成了高校的流行病，同時(shí)使考試成績(jī)?cè)桨l(fā)失去了學(xué)生學(xué)習(xí)成果和能力衡量指標(biāo)的意義。我們不知道更高的考試成績(jī)是否一定會(huì)帶來(lái)更高的教師評(píng)分，但單單是這種心態(tài)本身就會(huì)影響教師的行為。

????這種行為無(wú)非是一種互惠主義的體現(xiàn)——我?guī)土四悖ū热缃o你一個(gè)好成績(jī)），然后你再幫我（比如給我一個(gè)比較高的評(píng)分）。反正人類天生就有與人為善的習(xí)性，大家也不愿意被別人當(dāng)成一個(gè)難說話或者討厭的人。這讓人不禁去想，就像教師與學(xué)生、打車軟件的司機(jī)與乘客之間的互惠關(guān)系一樣，如果交易雙方都可以給對(duì)方打分，會(huì)是什么樣子。

????科技媒體TechCrunch的一篇文章指出，eBay在2008年通過評(píng)價(jià)體系改革消除了買賣雙方相互評(píng)價(jià)的可能。文章還指出，同樣一套房子在Airbnb（該網(wǎng)站允許相互評(píng)價(jià)）上的評(píng)分要比在TripAdvisor上高出14%（不允許相互評(píng)價(jià)）。該文章指出：“在不匿名的社會(huì)環(huán)境中，人們都想在別人眼里留下好印象，不愿意說別人的壞話，因?yàn)檎l(shuí)都不想讓別人覺得自己是個(gè)老是在抱怨的人，或老是在嘮嘮叨叨?！卑⒌?比坦也指出Uber上司機(jī)的得分都太高了，他認(rèn)為這也是互利評(píng)價(jià)的緣故，因?yàn)槟阒挥薪o別人一個(gè)極為正面的評(píng)價(jià)，別人才會(huì)投桃報(bào)李給你一個(gè)正面的評(píng)價(jià)。

????除此之外，“口碑經(jīng)濟(jì)”還有可能導(dǎo)致更加嚴(yán)重的問題。比如醫(yī)生為了獲得病人的好評(píng)，經(jīng)常會(huì)給病人做一些不必要的診斷測(cè)試，或是給病人開抗生素或強(qiáng)效止痛藥，特別是當(dāng)病人主動(dòng)要求的時(shí)候，而不管病人需不需要，有沒有用。也就是說，評(píng)分或?qū)υu(píng)分的預(yù)期改變了醫(yī)生的治療方法。“在南卡羅萊納醫(yī)療協(xié)會(huì)2012年的一項(xiàng)調(diào)查中，半數(shù)受訪醫(yī)生表示，由于面臨著需要提高患者滿意度的壓力，很多醫(yī)生不當(dāng)?shù)貫椴∪碎_了抗生素或麻醉劑?！被颊咴u(píng)分的流行與濫用麻醉劑之間是否存在某種關(guān)系，也是個(gè)值得觀察的問題。

????有辦法解決這個(gè)問題嗎？

????虛假評(píng)價(jià)，特別是那些比較極端和簡(jiǎn)單的虛假評(píng)價(jià)，是可以通過統(tǒng)計(jì)方法檢測(cè)出來(lái)的，只是目前技術(shù)還不完美。經(jīng)濟(jì)學(xué)家布萊恩?雅各布茨和史蒂芬?列維在一篇著名的論文中指出：“出乎意料的測(cè)試成績(jī)波動(dòng)和可疑的答案模式”，可以用來(lái)檢測(cè)教師是否為了提高學(xué)生的分?jǐn)?shù)而弄虛作假。正如我上文指出的那樣，Yelp、亞馬遜和谷歌等網(wǎng)絡(luò)公司都在努力消除虛假評(píng)價(jià)，比如通過構(gòu)建算法篩查出可疑行為等。

????亞馬遜采取了驗(yàn)證網(wǎng)購(gòu)評(píng)價(jià)者身份等策略，從而提高了水軍發(fā)布虛假信息的成本和難度。

????企業(yè)招聘新人和考核績(jī)效（這兩件事的本質(zhì)也是評(píng)估）時(shí)的做法提供了另一種有效的解決方案，即標(biāo)準(zhǔn)化的產(chǎn)品或服務(wù)評(píng)價(jià)指標(biāo)。米其林和普通食客對(duì)同一家餐廳的評(píng)價(jià)之所以非常懸殊，是因?yàn)槊灼淞值膯T工有一套更加正規(guī)的評(píng)價(jià)標(biāo)準(zhǔn)，以及一套確保這些標(biāo)準(zhǔn)能被嚴(yán)格遵循的流程。

????比坦的公司旨在幫助各種類型的企業(yè)獲得實(shí)時(shí)的顧客反饋，先發(fā)制人地解決服務(wù)問題，阻止負(fù)面評(píng)價(jià)。比坦為我們提出了兩條建議。她指出，如果人們不能匿名發(fā)虛假信息的話，他們就不大愿意那樣做了，所以身份驗(yàn)證可能是個(gè)有用的辦法。另外，由于很多明顯的原因，你的朋友和熟人提供的信息一般比陌生人更加有用和可信。不過在這個(gè)問題上，“也有些數(shù)據(jù)顯示，在北美，大多數(shù)人更相信網(wǎng)上的評(píng)論，而不是他們的朋友?！边@真不是一個(gè)好習(xí)慣。

????AdiBittan, a former Stanford MBA student and co-founder of OwnerListens, told me that there were two types of strategies that companies used: “white hat” and “black hat” approaches. “White-hat” strategies entail moves such as figuring out who your most satisfied customers are and then encouraging them—and even making it easier for them—to write reviews on popular websites. “Black-hat” strategies involve disparaging competitors, or maybe even future competitors. In one particularly notorious and well-known example, Chicago celebrity chef Graham Elliot’s “highly anticipated and oft-delayed gourmet sandwich/soft serve shop” got a 1-star review on Yelp from a prospective patron who said his “otherwise pleasant walk” was ruined by going to the establishment and finding that it was closed. The café had not even opened its doors for business at that point. Elliot, whose opinions of Yelp are essentially unprintable, took this as an example of how bad reviews are.

????There are more problems with the reputation economy beyond just manipulated and inaccurate ratings. The prospect of customer reviews can induce behaviors designed to increase customer ratings in ways that are not useful and are sometimes harmful.

????Returning to teacher ratings, there is a common belief, supported by at least some evidence, that one way to achieve higher ratings is for instructors to give the students who are doing the ratings higher grades. This belief produces the now-endemic grade inflation in higher education and also makes grades less meaningful as indicators of student achievement or ability. It’s unclear if higher grades produce higher teacher ratings, but the belief that this relationship holds nonetheless affects instructor behavior.

????This behavior is all about reciprocity—I help you out (for instance, by giving you a good grade) and you help me out (for instance, by giving me a high rating)—and the natural human tendency to be nice and the associated desire to not be perceived as negative or difficult. These ideas call into question what happens when, like with teachers or Uber drivers, you have counterparties in a transaction rating each other.

????An article in TechCrunch noted that eBay dispensed with reciprocal reviews in 2008 and also reported on a study that found that the identical property was rated 14% higher on Airbnb (that uses reciprocal ratings) than on TripAdvisor, which does not. That same piece noted: “People want to look good in social settings in which people’s identities are not anonymous, people tend to shy away from saying bad things because they don’t want to be the one who seems like a constant complainer or never-ending nagger.” The average Uber driver score is too high, according to Bittan, who believes that reciprocal reviews create incentives for being overly positive to get a positive review in return.

????And there are more serious problems than just giving higher grades or higher ratings to encourage others to help you out in return. Doctors seeking higher patient ratings are more willing to order (unnecessary) diagnostic tests or to prescribe antibiotics or potent painkillers even when not needed or helpful, particularly if patients request them. In other words, reviews or the prospect of being reviewed changes treatment: “In a 2012 survey by the South Carolina Medical Association, half of the physicians surveyed said that pressure to improve patient satisfaction led them to inappropriately prescribe antibiotics or narcotics.” It would be interesting to see if there is a relationship, both over time and across settings, between the prevalence of patient reviews and the growing problem of opiate abuse.

????Is there any way out of this problem?

????Cheating, particularly in its extreme or least sophisticated forms, can be detected statistically, albeit imperfectly. Economists Brian Jacobs and Steven Levitt, in a famous paper, showed that “unexpected test score fluctuations and suspicious patterns of answers” could be used to detect teacher cheating to artificially raise their students’ scores. As I noted above, Yelp, Amazon, and Google, among others, are all working to try to eliminate fake reviews, including by building algorithms to highlight suspicious activity.

????Amazon’s verified purchaser identification of reviews and related strategies help to raise the cost and difficulty of flooding sites with bogus information.

????The world of assessing job candidates and doing performance appraisals, both forms of rating, offer another useful solution: provide standardized product or service dimensions for evaluation. One reason Michelin and diners’ ratings differ is that the Michelin employees have a more standardized set of criteria to evaluate restaurants and a process to ensure that those standards are used.

????Bittan, whose company was established to help provide businesses of all sizes with real-time customer feedback, preemptively solve service issues, and head off negative reviews, made two other suggestions. She noted that people are less likely to engage in deception if they can’t do so anonymously, so requiring people to identify who they are might help. And she noted that, for many obvious reasons, your friends and even acquaintances are more likely to provide useful and honest information than are others. However, in this regard, “some data show that a good majority of people in North America believe and trust online reviews more than they trust their friends’ opinions.” Bad decision.