Monthly Archives: June 2008

The Maths of Pointless Numbers

In an idle moment in a place I cannot recall, but may have been the local takeaway, I read the Daily Express, an unusual event.  And I read an article entitled “CANCER RISK OF JUST TWO GLASSES OF WINE A DAY”  which demonstrated exactly why not the read the Daily Express if you wish to retain your sanity.

This is how the Express sensitively rendered the story…


The particular issue raised by this non-news story has been rolling around the back of my brain for a while, however the creative forces have been battling with perfectionist tendencies, fending off a full research project on the many different life risks, probabilities thereof, and the mechanisms of converting annual probabilities into life-time ones, and all manner of analytical delights.

So to break the log-jam (and get a life in between), I have crayoned  the issue, rather than the full Powerpoint…


You can find all sorts of stats around the web about the probability of different life risks if you look – here and here, for example, and tease out interesting, contrarian nuggets.  Such as,  drowning is much more likely than a fatal dog attack, yet  there are many strait-jacketing laws on dangerous dogs, but no UK inland rescue force to save people who fall in the water, which paradox seems to defy common-sense.

The issue in the case of the Australian report is that the risk that is being increased by 75% is diddly-squat to start with, and (Diddly-Squat * 1.75) = Sweet FA (in the Maths of Pointless Numbers).  It is undoubtedly bad if it actually happens, but the probability is not something you can, or should, let dictate your life.

I suppose headlines like “Medicos issue report about irrelevant statistical findings that don’t matter” don’t sell papers, so  there must be people who enjoy a little frisson of fear, panic and anxiety over their breakfast corn flakes, and prepared to read the Express to get it….

Of Washing Machines and Software Errors

The human brain is constructed so that it is very good at seeing patterns (even where there are none), and so “coincidentally” after my previous spat on the same topic, I have been suffering my own version of Call Centre hell this week – just trying to book an engineer to come and mend our ailing tumble-drier.

Last year, just about this time, I fell for the pitch of Domestic & General who sold me a three-in-one policy for kitchen equipment breakdowns. And so it came to pass that the Tumble Drier started thrashing itself to pieces, just after the renewal letter came through.

All should have been smooth: “direct debit”, “you need to do nothing”, “renew automatically” were the comforting phrases in the letter. Tchah!

To cut a long story short I lost a few precious hours of my life listening to on-hold music and all that other stuff, and then when I got through it was “that fine, just call blah on this number, oh, thats strange the policy has been renewed but the equipment shows it is lapsed, let me put you on hold”…

So clearly the renewal process had gone all agly, creating an insurance curate’s egg, in fact.

But the cherry on the cake was when I received a very cheerful automated email from D&G below…


Renew for a penny? Hmmm, aha, the light dawns, something has gone wrong with their arithmetic. Last years price was £119.88, nicely divisible by 36 (3 boxes x 12 months), this years price (up, of course) is £131.88 – oh dear, divide that by 36 and you get lots of 33333333333333333333333333s on the end. Add in a bit of truncation and you have a nice little problem building up. If they had charged me £131.76, maybe things would have turned out differently.

Nothing as serious as the Patriot missile failure, or crash of Mars Climate orbiter (Imperial/Metric System confusion), or others of that ilk , but my very own personalised, computerised, automated rounding error.

Aside: Spreading the cost of the £0.01 by direct debit. I laughed so much I nearly died….

I clicked on the button, of course, I had to, in for a penny in for a penny, so to speak; to see if I could make the whole problem go away, but a “technical error” on the web-site prevented me from completing the transaction!

So here is a little sign for the D&G development team to hang from their office wall to act as a reminder as they ply their daily toil…