Why brain-teasers don't work

Martha Gill's Irrational Animals column.

Question: Beulah died in the Appalachians while Craig died at sea. Everyone was much happier with Craig’s death. Why? Answer: Beulah and Craig were both hurricanes.

Irritating, isn’t it? Brain-teaser questions are all irritating. It’s not that the answers are hard, just that they’re set in a context you’d have to be odd to anticipate. They’re the verbal equivalent of the game where you offer someone a high-five only to slap them in the face, or of dating men in London. Only a hyperalert psychopath could expect to get it right.

But ever since Microsoft decided to use brain-teasers in recruitment interviews back in the 1990s they’ve been spreading like gas in a hermetically sealed kitchen from which you have exactly nine minutes to escape. Tech firms use them; banks use them; Oxbridge has always used them.

They don’t work for hirers, though. They also actively discourage good candidates and have long-term ramifications for a company’s ability to recruit, according to research that came out in October. After putting 360 participants through the mill, Chris Wright of San Francisco State University found that otherwise qualified workers are put off interviews that use brain-teaser questions because they see them as unfair and setting them up for failure.

More than that, Wright found, interviewers don’t know what to do with the answers. The questions are often open-ended with no clear solution, so employers are often impressed with how a retort sounds, rather than what it includes. With open-ended brain-teasers – “Is this a question?” – it’s the smart-arse “Only if this is an answer” that gets points, though I wouldn’t be surprised if the similar “Is your mum a question?” and “Is your face a question?” scored just as high. In Wright’s study, interviewers did a much better job of working out a participant’s skill level after hearing answers to conventional rather than puzzle problems.

In his book Thinking, Fast and Slow the psychologist Daniel Kahneman lists a few puzzles that it’s hard to get right. Here’s one: a bat and ball cost $1.10. The bat costs $1 more than the ball. How much does the ball cost? The answer most people give is ten cents: “intuitive, appealing, and wrong”. That would make the bat $1.10 ($1 more than the ball) and the total $1.20. The answer is five cents.

Not too difficult to work out, in the end, so why do people get it wrong? Kahneman says that it’s a question of motivation. Some people are simply lazy and some are, by nature, “engaged. More alert, more intellectually active, less willing to be satisfied with superficially attractive  answers, more sceptical about their intuitions.”

But I would go further. Some people are expecting to be asked a brain-teaser question and are trying to impress the questioner, and others are simply trying to end the encounter politely so they can get to the bar. If you’re in the latter category, what the brain-teasers are testing is your sensitivity to context. If you’re sensitive enough, you get the answers wrong. Of course you do. The questioner is indicating left. Why would you ordinarily turn right? It would be a monumental waste of energy to expect the unexpected all the time. Thank goodness most of us don’t.

Infant protégé? Photograph: Getty Images

Martha Gill writes the weekly Irrational Animals column. You can follow her on Twitter here: @Martha_Gill.

This article first appeared in the 05 November 2012 issue of the New Statesman, What if Romney wins?

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7 problems with the Snooper’s Charter, according to the experts

In short: it was written by people who "do not know how the internet works".

A group of representatives from the UK Internet Service Provider’s Association (ISPA) headed to the Home Office on Tuesday to point out a long list of problems they had with the proposed Investigatory Powers Bill (that’s Snooper’s Charter to you and me). Below are simplified summaries of their main points, taken from the written evidence submitted by Adrian Kennard, of Andrews and Arnold, a small ISP, to the department after the meeting. 

The crucial thing to note is that these people know what they're talking about - the run the providers which would need to completely change their practices to comply with the bill if it passed into law. And their objections aren't based on cost or fiddliness - they're about how unworkable many of the bill's stipulations actually are. 

1. The types of records the government wants collected aren’t that useful

The IP Bill places a lot of emphasis on “Internet Connection Records”; i.e. a list of domains you’ve visited, but not the specific pages visited or messages sent.

But in an age of apps and social media, where we view vast amounts of information through single domains like Twitter or Facebook, this information might not even help investigators much, as connections can last for days, or even months. Kennard gives the example of a missing girl, used as a hypothetical case by the security services to argue for greater powers:

 "If the mobile provider was even able to tell that she had used twitter at all (which is not as easy as it sounds), it would show that the phone had been connected to twitter 24 hours a day, and probably Facebook as well… this emotive example is seriously flawed”

And these connection records are only going to get less relevant over time - an increasing number of websites including Facebook and Google encrypt their website under "https", which would make finding the name of the website visited far more difficult.

2. …but they’re still a massive invasion of privacy

Even though these records may be useless when someone needs to be found or monitored, the retention of Internet Connection Records (ICRs) is still very invasive – and can actually yield more information than call records, which Theresa May has repeatedly claimed are their non-digital equivalent.

Kennard notes: “[These records] can be used to profile [individuals] and identify preferences, political views, sexual orientation, spending habits and much more. It is useful to criminals as it would easily confirm the bank used, and the time people leave the house, and so on”. 

This information might not help find a missing girl, but could build a profile of her which could be used by criminals, or for over-invasive state surveillance. 

3. "Internet Connection Records" aren’t actually a thing

The concept of a list of domain names visited by a user referred to in the bill is actually a new term, derived from the “Call Data Records" collected by hone companies. Compiling them is possible, but won't be an easy or automatic process.

Again, this strongly implies that those writing the bill are using their knowledge of telecommunications surveillance, not internet era-appropriate information. Kennard calls for the term to be removed form the bill. or at least its “vague and nondescript nature” made clear.

4. The surveillance won’t be consistent and could be easy to dodge

In its meeting with the ISPA, the Home Office implied that smaller Internet service providers won't be forced to collect these ICR records, as it's a costly process. But this means those seeking to avoid surveillance could simply move over to a smaller provider. Bit of a loophole there. 

5. Conservative spin is dictating the way we view the bill 

May and the Home Office are keen for us to see the surveillance in the bill as passive: internet service providers must simply log the domains we visit, which will be looked at in the event that we are the subject of an investigation. But as Kennard notes, “I am quite sure the same argument would not work if, for example, the law required a camera in every room in your house”. This is a vast new power the government is asking for – we shouldn’t allow politicians to play it down.

6. The bill would allow our devices to be bugged

Or, in the jargon, used in the draft bill, subjected to “equipment interference”. This could include surveillance of all use of a phone or laptop, or even the ability to turn on its camera or webcam to watch someone. The bill actually calls for “bulk equipment interference” – when surely, as Kennard notes, “this power…should only be targeted at the most serious of criminal suspects" at most.

7. The ability to bug devices would make them less secure

Devices can only be subject to “equipment interference”, or bugging, if they have existing vulnerabilities, which could also be exploited by criminals and hackers. If security services know about these vulnerabilities, they should tell the manufacturer about them. As Kennard writes, allowing equipment interference "encourages the intelligence services to keep vulnerabilities secret” so they don't lose their own access to our devices. Meanwhile, though, they're laying the population open to hacks from cyber criminals. 


So there you have it  – a compelling soup of misused and made up terms, and ethically concerning new powers. 

Barbara Speed is a technology and digital culture writer at the New Statesman and a staff writer at CityMetric.