30.11.13

News Numbers - Helipcopters

With plenty of numbers being used in the news, it's often very tempting to overplay the effect of the numbers, often quoting without some context.

Hence having personally coined the term "Numberator"....the use of a number without some necessary contextual denominator here's another example....Another of those news number naughties.... or news numberation.

So the UK is very helpfully sending aid to the Philippines to support victims of typhoon Haiyan.  HMS Darling is helping out but will be replaced by HMS Illustrious announces the Prime Minister...

"And I can announce today that once Daring has started its work, we are actually going to be able to replace in time HMS Daring with HMS Illustrious which is of course a carrier with helicopters, seven times as many helicopters as on HMS Daring and with the key ability to process fresh water. So we will be giving further assistance in the best way we can". 

So "seven times" as many helicopters, that's quite some emphasis.  That's also the edited sound bite that made the main news headlines.  So how many would that be in practice?

Actually it's seven helicopters in total.  HMS Darling had one and HMS Illustrious has seven.  So yes technically seven more.

"Seven times more helicopters" does seem to have a more powerful emphasis than "Seven helicopters". Seven times is a relative statement that can apply in multiple situations for higher numbers.  So if there were 2 helicopters on HMS Darling there could be 14 on HMS Illustrious, if 3 helicopters on Darling then 21 on Illustrious.    So while the relative statement can be applied for larger (and even much larger) scenarios, here it's applied in the lowest possible extreme scenario, but at the same time can, and arguably does, imply larger scenarios.  In the larger scenarios the "7 times" is helpful shorthand.  Rather than saying something in increased from 123 to 861, the "7 times" gives a better quicker sense.   So when we hear "7 times more" were more naturally drawn to assume it's shorthand for bigger numbers than simply 1 to 7.  

An there's another twist.  Of course while HMS Illustrious does have seven times more helicopters than the one on HMS Darling which is already deployed. The net increase in the Philliplines is of course only 6 extra helicopters.

One simple calculation step away from the raw data, but looses so much meaningful context in the presentation.  It's also a comparative measure rather than an absolute one.

This is a great simple demonstration of the powerful message around exploratory data analysis  The further we are from the underlying data, the greater the chances of misunderstanding and misrepresentation. Add to that the messages from the Statistical Process Control movement,  "No data has meaning apart from it's context".