Friday, 8 January 2016

Meet The Kid With An IQ Higher Than Most Other Kids In Her School Year

Meet the kid with an IQ higher than Einstein. And another one, and another one, and this one, and this one, and this one, and these ones.

Let's ignore the elephant in this room for now.

What's going on here with all these identical articles?

Firstly, IQ tests are valid, mainstream psychology, and anyone who takes Sam's joke seriously is completely ignorant of the literature. For more, my friend Stuart's book is a good introduction.

Secondly, we don't know what Stephen Hawking's or Albert Einstein's IQs were, since they never sat a full IQ test in controlled conditions. The estimations of their IQs are complete speculation, and should be ignored.

That said, these kids are getting very high scores. On commonly used IQ tests, results are standardised to a normal distribution, with a mean of 100 and a standard deviation of 15. 

With thanks to the website ''.

This means 34% of the population will have an IQ within one standard deviation above the mean (100-115), and another 34% one standard deviation below it (85-100). 162 is 4.1 standard deviations above the mean (z=4.1). Unfortunately can't cope with a child this smart, they're simply off the chart. But using a different normal distribution calculator, I came up with a percentage of 0.0021. That is, one in 48000. We live in a big country, so there will be plenty of people that smart, probably around 1300 in the UK.

I guess it's plausible there would be quite a few kids this smart, but most kids will never take an IQ test, even really smart ones, and why are they all 12 year old girls? And how did a single school have 56 of them?

The answer is that mensa don't use the more common IQ tests. They use one called the Cattell III. This test still has an average of 100, but the standard deviation is 24, quite a bit higher. This flattens the curve, the best will get higher scores, the worse will get lower (but are unlikely to take the mensa test anyway). The consequence of this is that a maximum score of 162 is much less impressive. It is 2.6 standard deviations above the mean, and so we would expect 0.47% of the population to get this maximum score. Translating this into the regular, st dev 15 scale, gives us a much lower score of 139.

That is, in a random sample of about 200 people, you'd expect someone to get this maximum score. It really isn't that impressive. Mensa accept the top 2% of the population, so for a large school to have 56 kids in that bracket is hardly surprising.

I guess it's far too much to ask that newspapers stop writing these identikit stories, but even most people even who know a bit about IQ testing aren't aware that the standard deviations are different, and that therefore the scores aren't immediately comparable. I don't want to say that their system is vanity scoring, it's administered in controlled conditions, and is much better than any online IQ test, but also it's basically vanity scoring.

Tuesday, 5 January 2016

Why Is Everyone Refusing To Talk About Blank?!

I imagine the reaction would be that twitter would go crazy, and there would be lots of people tweeting about it, probably some sort of big hashtag campaign. Maybe it would get over a thousand retweets!

I don’t have anything to add about the weirdos in a shed in Oregon, and I don’t have anything against Mr McElwee personally, he’s behaving the same way everyone else does. What I want to talk about is the phenomenon of thousands of people simultaneously talking about how everyone is ignoring their favoured topic.

But first, we need to take a short detour into neuroscience. When we make a movement, our motor system produces an internal copy of that movement called an efference copy. This copy can be used to predict the sensory consequences of our actions. Newton’s third law states that every action has an equal and opposite reaction. When I push on a door, I therefore feel the door pushing back on me. If the door pushes back in a way I didn’t expect, I can update my internal model of my actions to account for this. If the sensory feedback from the door is exactly as expected, it’s not especially important information. The only sensory information I’m interested in is that which is caused by external factors. Our brain therefore cancels this signal, and we don’t notice the door pushing back, allowing us to be more sensitive to other, more important and unexpected sensory information.

To demonstrate this experimentally, Shergill et al invented a tit-for-tat experiment with two participants. Each would apply a force to the other, and then the second person would do this back, always trying to match the previous force. Because of the cancelling of sensory feedback, we don’t notice how strong the force we apply is, and it always seems as if the other person is pushing back more. The force escalates. We see the same thing with children fighting. Even if neither is trying to escalate, eventually they hit each other harder just trying to match.

When a news story occurs, lots of people go on social media and survey the state of public opinion. Then they react to it. Often to point out that everyone is nowhere near outraged enough. The other team are the environment that we are interested in. Our own group are just the agents who respond to this, and therefore we pay no attention to the predictable feedback from our actions in a similar way to participants in the force match experiment. But everything starts from zero, there’s no background level of outrage until everyone has made their move, so a true account of the state of public opinion has to consider our response and that of our immediate circle. People like Mr McElwee don’t see themselves as part of the media environment, and they don’t take into account their own reaction to events at all when evaluating it.

Thus it looks as if most people are against us, and we need to fight extra hard to compensate. Add that to the fact we better distinguish individuals on our own side, and every fight becomes our ragtag gang of plucky misfits against the evil monolithic outgroup. And every fight escalates, because we never realise how hard we’re hitting.

To be clear, I’m not saying this is the exact same process on a neurological level. However the effects look very similar in practice, and it works as a nice analogy.

We can see a similar situation in the reaction to Hoax Boy. A child brings what looks like a bomb to school, there is a predictable security incident. The boy is fawned over as a genius and a hero and the President invites him to the White House. The reaction was not unpredictable, there are a large number of liberals out there very sympathetic to this sort of event, and currently lots of them have some power in the US. But people don’t take into account the force of their own response when judging the situation, and thus the story is still taken by some to show the dark heart of racism lurking in American society. Equally, twitter trolls angry when anyone points out anything remotely sexist or racist see themselves as completely separate from the general environment. It seems to them as if their opponents are powerful and unopposed, in spite of the fact that their own abusive reaction to this is an inevitable fact of life.

Imagine if the ingroup did this, twitter would be furious!

It is, it’s alway furious, because twitter is you.