Posted in decision maths, psephology

I don’t think that the benefit to one party or another is a valid reason to pick a voting system – but one of the features of AV is that it tends to select the least objectionable candidate. Here’s a simplified example. Let’s imagine we have four candidates contesting a

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Posted in statistics

There’s an excellent article by talking about a really interesting probability ‘paradox’ to do with summer births. It’s not really a paradox (as with a lot of probability, it makes perfect sense once you think it through), but the “at least one boy” puzzle was one of my favourites growing

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Posted in logarithms

(Photo courtesy of UN Development Program.) We’ve had a lot of noticeable earthquakes around the world in the last year or so – Haiti, Chile, New Zealand. Probably no more than usual, except that we notice them more – but that’s a topic for another day. Instead, we’re going to

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Posted in ranting

Here, let me get on this soapbox a moment Things that irritate me beyond end, number two in a series of, well, lots: grumbles about how “oh, it’s pointless teaching maths, you only ever use it to work out discounts in the supermarket and there are calculators on your phone

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Posted in algebra, geek pride, prime numbers

If you follow the great big geeks on twitter – and , I’m looking at you – you’ll have seen bits and pieces of discussion about prime birthdays. How to find your next prime birthday It’s your prime birthday if you’ve been alive for a number of days that happens

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Posted in algebra

Two things: the somewhat random-looking picture above is from The Moon Is Blue, a 1953 film that’s the first known reference to the ‘dating rule’ discussed here. Secondly, I don’t make any judgement about the validity of the ‘dating rule’ – you might find it a useful rule of thumb

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Posted in fractions

Good God, will you get your fractions sorted out? You’re meant to have been on top of them since primary school, but you’ve been studiously avoiding them for the last half-decade, haven’t you? If you’d put half as much effort into learning four simple rules as you have into convincing

Read More →… or, three easy steps to talking with your kids about $\sec(x)$1 If there’s one question parents dread more than “Where do babies come from?”, it’s “Can you give me some help with maths homework?” There are many possible reasons for this. The most common one I hear is “they

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Posted in triangles

pointed me at a puzzle by at MathsJam: or at the Science Punk blog. The question is: how many triangles are there in a ‘Mystic Rose’ shape like this one (right) – with six interconnected points. I reckon there are 110. I got this by splitting it up into different

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