Christmas Cake

There’s a shortage of Nintendo Wiis at the moment, because they’re popular and it’s Christmas. This has led to crazy people suggesting that Nintendo have engineered this shortage deliberately, which is true only in the rather weak sense that Nintendo’s objective is to sell consoles rather than horde them in shops. The fact is there’s no reason Nintendo would do such a thing - the only people who profit from a Wii shortage are canny eBay users. Nintendo make more money by selling more consoles. This is very basic stuff. Nintendo know this.

Nintendo’s PR company know this too, because they’re Very Clever Scientists. They’re a company called Cake, and they’ve done two pieces of Very Clever Science lately. The first was for Nintendo, and it was a study into how much energy you burn playing Wii. And it turns out, it’s not much. Though they have to be commended for doing a proper, albeit very small, trial and publishing the result anyway.

Cake’s other recent foray into the world of Very Clever Science was for The Children’s Society, a charity whose beliefs are fairly self-evident. They have issued a press release called “Have a mathematically perfect Christmas!”, in which they say (and you’ll have to imagine the phrase “sic” in brackets liberally sprinkled on this quote like some kind of Latin Christmas snow):

The University of Plymouth has Christmas all worked out! Professor & programme director of the School of Applied Psychosocial Studies, Rudi Dallos, has calculated the scientific theory for a perfect Christmas, it is: PX = 8F x 4P + 23£ x 8F + 3 G +3 W + 2W:3C + 5T:1NR _____________________________________________ 3D Professor Rudi Dallos devised the formula, which guarantees a perfect Christmas for families across the UK, to compliment the new Christmas book from The Children?s Society... The perfect Christmas formula (PX) considers the number of family members (F), cost (£) and number of Christmas presents given (P), number of walks taken (W), number of games played (G), the amount of wine and chocolate (W:C) consumed and the ratio of turkey to nut roast (T:NR)! Divide all that by the total days (D) you spent with your family and you have the perfect Christmas!

There are many, many things wrong with this, so let’s list just as many as we can find! But first, an aside. Obviously I’m in favour of charities in general, and I don’t know much about this one but it sounds like something I’d approve of, but this kind of thing is very bad for the public perception of science and while it annoys me when companies shit all over important things to turn a quick buck, charities should know better. I tend to think they should avoid doing things that will damage society, especially since they’re doing it on the back of donations. So, on with the list…

This is not a "scientific theory" until he has proved it. That's what the phrase "scientific theory" means.
If he did prove it, it would still not be a theory, because it is an equation. That would be a law. The theory would be the underlying mechanics. It is not possible to "calculate" a theory.
If it was possible to calculate a theory, and this was a theory, it would still not be true that Rudi Dallos had calculated this one. It would be more accurate to say that he had made it up, and more accurate still to say that he's whored his name out to it.
There is an equals sign in the numerator of a fraction. I am willing to give Dallos the benefit of the doubt here, as Cake's typesetting skills are not great (unless their client really does spell their name with a question mark). This is also, I assume, why the lower case letter 'x' is used in place of the multiplication sign, and why a row of underlines are used in place of division. And to be fair, their typesetting is just marvellous compared to The Daily Mail's version of this formula, which not only replicates this error, but duplicates the division so that revellers have to spend nine days with their families every day in order to have the prefect Christmas.
The symbol "W" is used for two quite separate quantities.
The pound sign goes before the number, genius.

And then there’s the subtle stuff. Some people have suggested that this equation suggests that one can have an infinitely good Christmas by spending zero days with the family. Personally, I think that’s reading it wrong. The letters are really units rather than variables. I think this is really a definition of a new constant PX, which is in the unusual mathematical units “man (presents + pounds) + games + walks + ml/g + turkeys per portion of nuts) per hour’. (In the Daily Mail’s version, this is per hour squared, making it some kind of bizarre festive acceleration constant, like a kind of Yuletide gravity. Possibly you are expected to buy everyone four more presents every day for nine days, a bit like Hannukah or that Twelve Days Of Christmas song.) That said, it’s still open to the same kind of abuse – if you don’t drink alcohol then you can’t have any chocolate or else the ratio is upset (that, or you have to have some chocolate to prevent undefined divisions), and if you only have one family member then you have to counter this by – I swear this is what it says – spending only 9 hours with them, and in that time playing three eighths of a game, taking three eighths of a walk, eating 166% more chocolate and nut roast than you’d really like.

If you want to spend less than £23 on each of your presents, you can compensate by spending less time with your family so the ratio is the same, however to balance the rest of the proportions, you also have to give proportionally fewer presents, go on fewer walks, and play fewer games. And eat more chocolate and less turkey. It also places no upper limit on how drunk you can get provided you’re willing to balance it with chocolate.

What we have here, you see, is not maths. It’s one of those crappy adverts that says “you plus our product equals profit er I mean happiness”. “The perfect Christmas is 4 presents each for 8 family members, £23 each for 8 family members, 3 walks, 3 games, 5 times as much turkey as nut roast and 3 times as much chocolate as wine, all over 3 days.” It’s nothing more than a description of a perfectly nice Christmas phrased a bit like maths. Then written as a formula.

And it can piss off.