# Archive for category Does not compute

### How to inflate figures and scandalise people

Posted by atomicspin in Damned lies and statistics, Does not compute, Food is totally science, Health & medicine on Wednesday, 20th July 2011

A number of papers this week (*Daily Express*, Daily Mail, Daily Mirror, Daily Telegraph, Wales on Sunday*) have all carried the same story, claiming that, in the words of the Daily Mail, “NHS officials pay £32 for gluten-free bread that costs £2.25 in the shops”.

Though it’s not impossible that a big organisation like the NHS has inefficient bread-buying schemes, it seems a bit unlikely that something as widely prescribed as gluten-free bread is being bought for more than 10 times its shelf price. So where did the figures come from?

Well, it looks like the story comes from this Welsh government data about prescriptions. Sure enough, if you look it says that the 27 prescriptions of a particular type of bread, Lifestyle Gluten-Free High-Fibre Brown, cost £32.27 each.** *But* doctors aren’t prescribing one loaf of bread at a time.

The important column is the one marked “quantity”, which tells you how many grams of bread were prescribed. For Lifestyle Gluten-Free High-Fibre Brown, doctors prescribed a total of 123,600 grams. Divided between the 27 people, that’s 4,577 grams each, or about 11 loaves of bread per person. So that £32.27 figure is the cost of buying **11** loaves of bread, not 1, and as the Welsh government points out, it works out at around £2.82 per loaf. This is still slightly more than the cheapest online cost of the bread, so I assume there is still room to bring prescription costs down, but NHS Wales is certainly not spending more than £30 on a loaf of bread.

* Turns out James Delingpole writes for *The Express* too. Huh.

** If you want to check for yourself, it’s in section G-O under the name “Lifestyle_G/f H/fbre Bread Brown”.

### Happy birthday Neptune?

Posted by atomicspin in Does not compute, Me being pedantic, Metric and measurement, Space and astronomy on Sunday, 10th July 2011

Just a quick post: according to *The Observer*, tomorrow (July 11) will be one Neptunian year since the discovery of the planet Neptune. Except…

One year on Neptune is 60,190 Earth days. Neptune was discovered on 23 September 1846, so Neptune’s first birthday will be 60,190 days after this date.

23 September 1846 + 60,190 days = July 10, 2011

Neptune’s birthday is today, not tomorrow! We’ll all be celebrating on the wrong day!

Never mind phone hacking, this is the ** real **scandal.

**Edit:** The BBC is **even more wrong**, claiming Neptune’s birthday is July 12. The philistines!

**Double edit:** In fact, it looks like we’re all right! July 10 is one average Neptunian year after the date of discovery, July 11 is the day when Neptune will have made precisely one orbit around the solar system’s barycentre (i.e., its centre of mass when you take the Sun and all the planets into account), and July 12 is the day that Neptune will have made precisely one orbit around the Sun. (A figure of July 13 is floating around as well, most likely as a result of an Indian newspaper article which has taken timezones into account). Thanks to Up, Blogstronomy and the Wikipedia users on Talk:Neptune!

### A bumper crop of nonsense equations in the Mirror

Posted by atomicspin in Churnalism, Conflicts of interest, Damned lies and statistics, Does not compute on Friday, 27th May 2011

This piece is only in the print version of the Mirror as far as I can tell, but it’s so daft I can’t let it go. Equations! Loads of them! All bollocks!

First:

**Tractors:**

*q* = (*v*_{c} – *v*_{s})*k*_{s}

This formula, produced by University College London and the Green Flag breakdown company, tells you how long you spend stuck behind a tractor, where *q* is the time spent, *v _{c}* is the speed of your car,

*v*is the speed of the tractor and

_{s}*k*

_{s}is the number of tractors you meet per journey.

The trick to explaining why this is bollocks is something called dimensional analysis. Basically, since we’re trying to work out how long we spend stuck in traffic, the result should be a time. Instead however, we have speed, measured in miles per hour – ie, distance per time – times number of tractors. This is not a time – we’ve still got that pesky distance in there which we haven’t got rid of. Therefore, this formula is nonsense.

**The perfect bacon sandwich**

*N* = *C* + {fb(*cm*) . fb(*tc*)} + fb (*Ts*) + fc .* ta*

This came from Leeds University, who reportedly spent 1000 hours tasting 700 variations of bacon sandwiches to make this formula. All I’ll say is that that works out at 1 hour 25 minutes per sandwich. They must be very slow eaters.

The formula itself, as described by the Mirror, are meaningless. Those fbs and fcs are “functions of the bacon type”, which are never explained. *cm* represents condiments (if you can tell me what “7 + ketchup” equals, you’re a better mathematician than me), *tc* is cooking time, *Ts* is temperature, *ta* is the time taken to fill the sandwich and *C* is the force (in Newtons) required to break the bacon.

Since we don’t know what fb and fc is, I haven’t a clue how the units work, but if fb can be a function of time, temperate *or* condiment, this must be a very versatile function!

**The perfect cheese sandwich**

W = [ 1 + ((bd)/6.5) - s + ((m - 2c)/2) + ((v + p)/7t)] (100 + l/100)

Now, at least the dimensions more or less work in this one, from Bristol University and, apparently, a cheese company. This tells you, supposedly, the thickness of cheese in the perfect sandwich (in millimetres). b is the bread thickness, d is the “dough modifier”, s is the thickness of the of the margarine, m is the thickness of the mayonaise (and c is the creaminess of the mayonaise), v is the thickness of the tomato, p is the thickness of the pickle, t is the tanginess of the filling and l is the lettuce thickness.

If you look at this one, at least all the things that are being added together are thicknesses (except for the “creaminess”), so our end product is also a thickness!

Of course, it doesn’t say how you assess “dough modifier”, “creaminess”, or “tanginess”. The company’s website has an online calculator (it’s viral marketing, so I’m not sute I want to link it, but, err, here it is, just don’t buy cheese from it!) which does the equation for you, but you never actually have to use the creaminess modifier, so that’s no help.

**The best way to open champagne**

P = T/4.5 +1

This is actually a good one. P is the pressure in the bottle in atmospheres, T is the temperature of the champagne in centigrade. It’s only an approximation, so it falls apart at very high or low temperatures, but around room temperature, it actually works alright. At 4.5 degrees, the pressure is 2 atmospheres, at 9 degrees it’s 3 atmospheres, and at 18 degrees it’s 5 atmospheres. This tallies pretty well with the figures in the *Mirror* and on this site. One point for the *Mirror*!

**The perfect joke**

x = (fl + no)/p

Ah, back to form. Supposedly, x is the funniness of the joke, f is the funniness of the punchline, l is the length of build up, n is the number of times the comedian falls over, o is the “ouch factor” and p is the number of puns.

One obvious problem: if your joke has no puns, p = 0, so you’re dividing by zero and your joke is infinitely funny!

One other obvious problem: according to this, longer jokes are ALWAYS funnier than shorter ones. So according to this formula:

“A man walks into a bar. Ow.”

Is nowhere near as funny as.

“A man walks down the street. It’s a bright early summer’s day, and a few clouds scud across the afternoon sun. Thirsty, he decides to go for a drink and walks into a bar. Ow.”

One more obvious problem: increasing the ouch factor supposedly ALWAYS makes the joke funnier. So if the comedian trips over, that’s slightly funny. If he gets hit with a frying pan and keels over, that’s funnier still. And if he falls out of a third story window, lands on the concrete below and breaks both his legs, his pelvis and three vertebrae, that should be utterly hilarious!

So in other words, if you were to use this to produce the perfect joke: a man tells a longwinded monologue – but with no puns – while repeatedly suffering debilitating injuries. Since delaying the punchline increases funniness too, the punchline should NEVER come. Monologue, no puns, no punchline, repeated torture. Sounds like my sort of thing!

**The perfect amount of gravy for Sunday lunch**

(W – (D/S))/D x 100

Where W is the weight of the uncooked food, D is the weight of the cooked food, S is the amount your food shrinks.

I can kind of see where they’re coming from on this, but what the formula is trying to do, basically, is tell us how much water the food has lost during cooking (though I can’t make sense of the dimensions here – I don’t know whether it’s telling us the weight of the gravy, the amount of gravy, or what). This isn’t the same as the perfect amount of gravy. For example, chips lose very little weight during cooking, but if anyone tells me that chips shouldn’t be absolutely smothered in gravy then that is CRAZY TALK.

**Pulling a cracker**

O = 11 x C/L + 5 x Q

Where O is the angle(?) C is the is the circumference of the cracker, L is the length, and Q is the quality of the cracker (1, 2, 3).

The dimensions work in this one, but I can’t really make any sense of it. The better quality your cracker is, the lower the angle you pull it at? I guess it’s meant to say that thicker crackers need a stronger pull. I’ll give this one a maybe.

Anyway, everyone knows the secret is to twist the opponent’s end of the cracker before you give it to them.

**The perfect holiday beach**

(A x W) + 2[E x C x V] + v[F x S] / (T + TC)

Sigh.

A is the quality of the beach, W is the weather, E is the entertainment, C is the culture, V is the activities, F is the familiarity, S is the shopping, T is the time to destination and TC is the cost of the holiday as a percent of your income.

Great. And if anyone can tell me what entertainment times culture times activities is, or why, if all of these are so subjective, the *Mirror* can just crown the Tuscan Rivera the best, I’d be delighted.

(And if familiarity makes a beach better, are you not allowed to go to new beaches?)

**The perfect sandcastle**

OW = 0.125 x S

OW is the amount of water, S is the amount of sand.

This barely counts as equation. It literally just says “use 8 parts sand to one part water”. Moving on.

**The perfect neckline**

O = NP(20C+B)/75

O is the “naughtiness”, N is the fraction of nipple showing, P is the percent of exposed frontal area, C is the cup size and B is the bust measurement in inches. If O is greater than 100 then the neckline is “obscene”.

Well, the most obvious problem with this is simple: have you got big breasts? Congratulations, you’re automatically more “obscene” than a smaller breasted woman wearing the exact same outfit. That’s a great message to be sending out, *Mirror*!

Secondly, there’s that “nipple fraction” parameter. If the nipple fraction is 0, the naughtiness is also 0. So if you walked around completely topless, save for a pair of pasties, that would be completely prim and proper.

In fact, even if you walked around topless, so N = 1, P = 100, you would need to be at least a 36 B or 34 C for that to count as “obscene”! (and that’s ignoring the fact that band size over-estimates the underbust measurement by several inches)

**Conclusion**

Sometimes I wonder if it’s worth getting worked up about these things. After all, it’s all a bit of fun (and advertising. Always advertising).

The thing is, though, this is why people hate maths. When people think of maths, they don’t think of the really interesting stuff – like the beauty of fractals or using the power of statistics to win thousands on the lottery. They think of dull formulas, spending hours in school plugging numbers into them and rearranging them without ever really understanding them.

When done properly, a formula shouldn’t just be a bunch of unintelligable letters, without any deeper meaning. A formula should be able to speak just as loudly as words do.

E=mc^{2}, for example, isn’t just a formula to plug numbers into. It also tells us that energy, *E*, and mass, *m*, are one and the same. You can destroy mass to create energy – as happens in a nuclear bomb – and you can use energy to create mass – so as you go faster, you get heavier (though sadly this is only noticeable when you get close to the speed of light, *c*).

That’s a lot of information packed in three letters!

### More PR survey junk from npower

Posted by atomicspin in Churnalism, Does not compute, Psychology on Tuesday, 21st December 2010

So WordPress managed to lose the text of this post. I don’t have time to rewrite it, so here’s the jist:

This is a pointless npower press release about how everyone supposedly wastes a whole every day worrying, plugging boiler repair. Of course, this is basically meaningless – no-one could remember or quantify exactly how long they spend worrying each day, so they’ll just give random numbers.

This didn’t stop the *Daily Express* uncritically repeating this interesting claim.

Because today was just *so slow* news wise.

Incidentally, this isn’t the first time *The Express* have printed an npower press release as news.