When it comes to toothpaste commercials, you've probably heard claims like, nine out of 10 dentists recommend "Brighter, Whiter." Or maybe it's four out of five or 80 percent. But either way, these companies expect you to see a wall of white coats, trust their authority and think no further.
當談到牙膏廣告時, 你大概會聽到像是這樣的說法: 九成的牙醫推薦「更亮、更白」。 或者可能是80%。 但無論如何,這些公司都希望你 見到醫師白大褂排成的牆, 相信權威,不再繼續追究。
Now that approach is basically BS, and you probably know it's BS, but the question is: How can you trust your BS radar?
那是胡說八道, 而且你大概也知道是胡說八道, 但是問題在於: 如何相信自己辨識胡說八道的雷達?
[Am I Normal? with Mona Chalabi]
[我正常嗎?莫娜·查拉比曲]
Well, when I'm faced with suspicious statistics, I tend to ask myself three questions. First, what were people actually asked? Sometimes the question that is put to survey respondents is wildly different than the one that ends up on posters and billboards. For instance, in 2007, one toothpaste ad in the UK claimed that more than 80 percent of dentists recommended their products. What that sounds like is that a majority of dentists prefer their product over all others, that those dentists were asked if this was the best product. But when the Advertising Standards Authority looked into it, they discovered that the dentists were asked to recommend several toothpastes, not one single choice. In fact, another brand was found to be almost as popular. To no one's surprise, the ad was deemed misleading.
嗯,當我面對可疑的統計數據時, 我習慣會問自己三個問題。 第一,人們真正問的是什麼? 有時候向調查對象提出的問題 和最終出現在海報和廣告牌的問題 大不相同。 例如,2007年英國的一則牙膏廣告 宣稱超過80%的牙醫 推薦他們的產品。 這聽起來像是 大部分的牙醫喜歡他們的產品, 而那些牙醫會被問到 推薦的牙膏是否是最好的牙膏。 但是當廣告標準局調查時, 他們發現牙醫們 被要求推薦幾種牙膏, 並非只有一種。 事實上,另一個品牌 幾乎一樣受到歡迎。 不出所料, 這些廣告被認為具有誤導性。
Now, the second question to ask is: What aren’t you telling me? In the 1970s, a sugarless gum company claimed that four out five dentists recommended their product. Now, their slogan was pretty upfront about the fact that these dentists were only recommending the product to people who already chewed gum, but they weren't so forthcoming about the fifth dentist. Decades later, the manufacturer made fun of it in a new ad campaign where they blamed the fifth dentist's different thinking on a freak accident, like a sudden squirrel bite. Now, since I'm all about the deviations in the data, I decided to look into this a little bit further. In fact, it's not that the fifth dentist recommended chewing sugary gum. What they don't say is that most of them recommended that their patients don't chew gum at all.
現在,要問的第二個問題是: 你隱瞞了什麼? 在1970年代,一間無糖口香糖公司 宣稱五分之四的牙醫 推薦他們的產品。 他們的標語直稱 這些牙醫只推薦這項產品 給已經嚼口香糖的人, 但沒透露第五位牙醫的看法。 十年後,製造商在新的廣告中 幽默地解釋此事, 將第五位牙醫不同的想法 歸咎於怪誕的意外, 像是有松鼠咬過。 由於我特別關注數據中的偏差, 因此決定更深入探究一下。 事實上,並不是第五個牙醫 推薦去嚼含糖的口香糖。 他們沒說的是那些牙醫 全都建議患者根本不要嚼口香糖。
The last thing to ask is: What was the survey context? Because there's a really big difference between saying "nine out of 10 dentists agree," and "nine out of these 10 dentists agree." Size matters and so does methodology. According to the American Dental Association, there are about 200,000 registered dentists in the US. I’m not going to bore you with the maths here, but to get a statistically significant sample of 200,000 people, you need about 400. So if you're reading in the fine print that only 50 dentists were surveyed, you know that's not statistically significant. It's just a marketing ploy.
最後一個要問的是: 問卷的背景是什麼? 因為以下這兩句大不相同: 「十個牙醫中有九個同意」 及「這十個牙醫中有九個同意。」 調查規模及調查方法都很重要。 根據美國牙醫協會, 美國有約二十萬名註冊的牙醫。 我並沒有要在此用數學 使你感到厭煩。 但要得到這二十萬人中, 統計上較明顯的樣本, 必須要有四百人接受調查。 因此如果小字寫著 只有五十人參與調查, 你便知道這統計並不顯著。 這只是個行銷策略。
So the next time you see one of these ads, ask yourself: What were people actually asked? What's gone unsaid? And what was the survey context? Hopefully, with those three questions and a little bit of skepticism, you will be able to understand when the data is legit and when it's irrelevant. Nine out of 10 Monas agree. [*No such survey took place]
因此下次你看到這種廣告, 問問自己: 這些人實際上在問什麼? 有什麼沒說的? 調查的背景是什麼? 希望透過這三個問題和一些質疑, 你可以了解何時數據會是正確的, 及何時會是無關緊要的。 十分之九的聽眾都同意。 [Monas 沒進行此類調查]