{"id":90687,"date":"2018-10-15T15:09:42","date_gmt":"2018-10-15T13:09:42","guid":{"rendered":"https:\/\/www.erasmusmagazine.nl\/en\/?p=90687"},"modified":"2025-12-19T11:23:07","modified_gmt":"2025-12-19T10:23:07","slug":"how-numbers-can-compel-charm-and-mislead-us","status":"publish","type":"post","link":"https:\/\/www.erasmusmagazine.nl\/en\/2018\/10\/15\/how-numbers-can-compel-charm-and-mislead-us\/","title":{"rendered":"How numbers can compel, charm and mislead us"},"content":{"rendered":"

The book \u2018The best-selling book of all time (with this title)\u2019 by former EUR doctoral candidate Sanne Blauw (31) will be released on 30 October. In her book, Blauw, currently a journalist for De Correspondent, warns the public at large to not blindly trust all the numbers served up to us. \u201cNumbers are like a bar of soap: squeeze too hard and they\u2019ll slip out of your hands.\u201d<\/p>\n

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Sanne Blauw <\/span><\/p><\/figcaption><\/figure>\t

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Sanne Blauw (1986) grew up in Zeeland, left Middelburg after completing secondary school to spend a year in Rome, and subsequently studied Econometrics at Erasmus School of Economics (ESE). During her studies, her activities included membership on the University Council.<\/p>\n

After successfully obtaining her doctorate for her dissertation (Well to do or doing well) at ESE in 2014, she chose to pursue a career in Journalism. Since 2015 she has been working at the online medium De Correspondent as a correspondent investigating and clarifying numerical and statistical findings.<\/p>\n\n\t<\/div>\n

With the appropriate amount of scepticism<\/h2>

An Erasmus MC press release headline on Tuesday, 25 September regarding a study about smokers and ex-smokers blares: \u2018Screening can save thousands of lives\u2019. With much fanfare, the academic medical centre announced that conducting a CT scan every few years among smokers and ex-smokers leads to earlier detection of lung cancer. This reduces the chance of dying from this disease.<\/p>\n

But following a critical article in de Volkskrant the next day, the new, slightly less bombastic headline now reads: \u2018Lung cancer screening with CT prevents deaths\u2019. Because it turns out that while there were significantly fewer deaths from lung cancer in the screened group, the total number of deaths \u2013 from 934 to 904 \u2013 is not a significant difference.<\/p>\n\n\t

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\n\t\t\u2018The errors in the Erasmus MC press release tick all the boxes in terms of what I write about in my book\u2019\n\t<\/blockquote>\n\n\t<\/figure>\n\t\t<\/div>\n\t<\/div>\n

But you could even cast doubt on that, says Sanne Blauw, about a week later in a cafe at Amsterdam Central Station.\u00a0The reason for the interview is her book \u2018The best-selling book of all time (with this title)\u2019 slated to hit the shelves later this month. Her engaging writing style reveals how numbers can compel, charm and mislead us. In short, she\u2019s trying to point out to us mortals that the barrage of numbers thrown about by manufacturers, scientists, politicians and media should not be thoughtlessly accepted as the truth. Or put more accurately, they shouldn\u2019t be considered true or untrue at face value. Instead, they should be met with the appropriate amount of scepticism.<\/p>\n

A good example is the Erasmus MC press release about screening smokers and ex-smokers. \u201cThe errors in this press release tick all the boxes in terms of what I write about in my book,\u201d says Blauw. \u201cFirst of all, the party issuing the press release has a huge vested interest regarding the result, even if it\u2019s only the large amount of money involved in the study. Second, the information was publicised at a convention, while no justification of the research was given and the research hadn\u2019t even been published yet. Believe me, this is completely unacceptable. And the way the numbers were collected was also not representative, and there was an unsupported extrapolation that thousands of deaths could be avoided. There are numerous errors to be found in their claim.\u201d<\/p>\n

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The book is only published in Dutch<\/span><\/p>

\n\t\n\n<\/svg>\n<\/span>\n\tImage by:<\/span>\n\n\t\t\t\n\t\t\t\t\t\t\tde Correspondent<\/span>\t\t\t\t\t<\/span>\n\t<\/p>\n<\/figcaption><\/figure>

To manipulate <\/h2>

However, Blauw is not surprised by such cases. Since swapping academia for a career as a journalist four years ago, she now works as a \u2018numbers sleuth\u2019 for de Correspondent. Since then she has seen her share of questionable research figures and dubious polls cross her path. Sometimes it\u2019s a brewery-sponsored study into the effects of alcohol on health. Or intelligence tests with biased questions and experiments using atypical random sampling. All these topics are discussed in her book.<\/p>\n

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Sanne Blauw <\/span><\/p><\/figcaption><\/figure><\/div>

In itself, there\u2019s nothing novel about the subject matter. Whenever numbers are used to explain something, there is always scope to manipulate the findings, and someone will write to expose this manipulation. A good example is Darrel Huff\u2019s brilliant \u2018How to lie with statistics\u2019 published in 1954. Blauw agrees that this is indeed the case, but she feels it can\u2019t hurt to refresh people\u2019s memory with a slightly more user-friendly work on the topic. In fact, since Huff\u2019s book was published, essential psychological insights have been unearthed regarding the relationship between humans and numbers. These insights have been incorporated in \u2018The best-selling book of all time (with this title)\u2019.<\/p>\n

\u201cThese misunderstandings persist, so I felt it was time for a new book,\u201d explains Blauw. She can also get quite worked up when she sees what can go wrong, and in this sense, she\u2019s a woman on a mission. \u201cThere\u2019s often a lack of knowledge among those on the receiving end of numbers. A lot of people have math anxiety and find numbers intimidating. At the same time they are also guilty of misinterpreting numbers because they are guided by their gut feelings. The book illustrates this perfectly in a case revealing how political affiliation actually influences how numbers are interpreted. In the US, Republicans frequently take the position that stricter gun control measures don\u2019t work. This was also the case among a group of Republicans who were presented with numbers that could be interpreted to support the opposite of their position. The same could be observed among Democrats: they were more likely to see a reduction in crime even when this wasn\u2019t supported by the numbers.<\/p>\n\t

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Questions to ask yourself when you come across a number somewhere:<\/p>\n

1. Be aware of your gut feeling regarding the number
\n2. Who came forward with the number?
\n3. What choices were made when measuring?
\n4. How were the numbers compiled?
\n5. How were the numbers analysed?
\n6. How are the numbers presented?<\/p>\n\n\t<\/div>\n

The creeping feeling that life is more complex than numbers<\/h2>

Blauw is now aware of why we let ourselves be misled by numbers: \u201cWe assume that numbers are objective evidence, but that\u2019s not the case. We think that numbers are very precise and leave no room for doubt or grey areas. But of course that\u2019s not true.\u201d That\u2019s why Blauw\u2019s book opens with a scene where she recounts an interview with the Bolivian cleaner Juanita. The interview is for her Economics doctoral research into happiness and income disparity.<\/p>\n

\u201cIt turns out the survey I concocted on the eleventh floor of the Woudestein campus wasn\u2019t really adequate. And that\u2019s when I first got the creeping feeling that life is more complex than numbers. Here I was, sitting across from a flesh-and-blood person who was saying things I couldn\u2019t express with numbers.\u201d<\/p>\n

Blauw slowly came to realise she was more interested in the stories behind the numbers rather than the numbers themselves. Remarkable, in light of her fascination with numbers, even as a child. She initially wanted to study medicine, but upon seeing a classmate\u2019s copy of the econometrists\u2019 bible \u2018Calculus\u2019, she opted to study Econometrics. Perhaps the seed that led to her now deciphering rather than manipulating numbers was sown in her interview with Juanita all those years ago.<\/p>\n

A series of \u2018mistakes\u2019<\/h2>

In her book she uses William Bruce Cameron\u2019s adage \u2018Not everything that counts, can be counted. Not everything that can be counted, counts\u2019 to show that what you measure is contrived, based on bias, and often ultimately expressed in just a single number. This is the case whether we\u2019re talking about someone\u2019s IQ, global warming, or the probability percentage of dying from a particular disease.<\/p>\n

This opens the floodgates for a series of \u2018mistakes\u2019. The research conditions or the questions are unsound, the composition of the research population for the study is not representative or large enough, margins of uncertainty are overlooked (deliberately or unintentionally), and last but not least, the party producing or disseminating the numbers has a vested interest in the findings.<\/p>\n

All things considered, by her own account and in keeping with her personality, Blauw doesn\u2019t fall into the trap of rejecting numbers altogether, in spite of the fallacies, gut feelings and vested interest that can almost always be found lurking in the background. \u201cI\u2019m not anti-numbers or anything like that,\u201d she says. A sentence in her book says numbers are no more than a window to reality. \u201cBut even so, the window pane isn\u2019t always fully transparent.\u201d<\/p>\n\t

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\u2018Het bestverkochte boek ooit (met deze titel)\u2019 will be available for purchase on 30 October; 208 pages; price \u20ac18.00; ISBN 9789082821642; published by De Correspondent. Read more at De Correspondent<\/a><\/em>. (Dutch only)<\/p>\n\n\t<\/div>\n\n\t

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De redactie<\/h2>\n\t\t\n\t\t
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