Sharks on an Ideal Plane

There gets to a point when writing a PhD chapter, when you are on your third gin and tonic for the evening, that one should turn one’s attention outwardly. I’d like very much to share thoughts about my research but the very first thing they teach you in PhD school is that no-one else is interested in your topic, by virtue of being so obscure that it bears no relevance to the lives of others.

Instead I’ll do some calculations.

It seems to me rather odd, in this age of missing planes and controversial shark attacks, that interested parties (airlines and environmentalists, etc) frequently employ statistics to reinforce the fact that these events are exceptionally rare. And yes they are, by-and-large, though perhaps the most spectacular evidence that all is not what it seems, lies in the massive differences of the massive orders of magnitude in such material. And if one person is fit to recognise improper uses of statistics it is I, largely through my own severe transgressions.

Sharkplane

Had I used the right shark, I could have called this picture ‘Tiger Airways’ and been appropriate on so many levels.

Earlier this year I came across a promotional poster actually pitting plane crashes and sharks against each other – in favour of sharks I believe (something to the order of hundreds/thousands times more likely to crash than be consumed), which piqued my interest as these are two of my more intimate* fears, and also as I touched upon with that shark-toaster comparison a while ago, I realised that there are far, far, far, far too many factors in plane-shark relations to effectively compare them.

So let’s compare them.

* By intimate I mean that the number of dreams I’ve had involving planes and plane crashes are literally equal. I think become so accustomed I’d be super-demure if I was involved in an actual fiery descent. And also I’ve had a youthful encounter with a carpet shark in the wild and watched Jaws a little early.

Probability of death in an air accident if you never fly and permanently reside in a bomb shelter or other secure underground complex: Approximately 0

Probability of death via shark attack if you never go in or near any sizeable body of water, nor be near a shark in transit, nor otherwise encounter a shark: Approximately 0

Probability to ensure a plane accident (1): Assuming consecutive 1 hour flights you’d need 114.077 years according to some calculations. Given there are a handful of verified people who have lived past that age, you could potentially spend your life working towards that particular goal.

Probability to ensure a shark encounter (1): Assuming 1 million life-threatening sharks (according to my last ‘study’) each with a 5km blood detection range (78.54km^2) equally spaced, makes for a 78 537 816 km squared area of ocean currently under shark-veillance; meaning 23.42% of the world’s oceans are currently detectable by sharks. Totally inaccurate, but let’s go with it. Assuming a cruising speed of 8km/hour in straight lines, it would take our imaginary shark formation 19.635 hours to leisurely cover an entirely new 23.42%, and 84 hours to complete detecting all the earth’s oceans. So if you were adrift in the ocean, basically in the time for an equally-spaced shark to ‘certainly’ detect you (3.5 days) you’d be dying from, ironically, thirst.

We're going to need a bigger boa. :D

We’re going to need a bigger boa. 😀

So in fanciful summary, both planes crashes and shark attacks are something you could (I guesstimate) live to reasonably expect, but only towards the very end of your life in each situation. However, if you took to human shark-baiting in convenient instalments, it would become much more attainable, and there is probably a strong correlation between amount of human-shark numbers/proximity and attacks, whereas flights are more quantitative and can only take finite passengers (one hopes). Anyway, the moral is that both these situations could conceivably become either a statistical certainty OR a statistical impossibility, depending on person, country, airline choices, frequency, stupidity, rugged determination, weather, preferred swimming times, etc, etc, etc.

So don’t.

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Shark/Toast Relativity

Toasters vs. Sharks… Their complex relationship has been hinted at both in documentaries and articles, with the outcome generally being that toasters are considered the more dangerous of the two. Statistically this is correct… Let’s assume the above sources are accurate; a global maximum of 15 fatal shark attacks per year compared to 300 fatal toaster ‘incidents’ per year (down from 3000 when first introduced!). It is therefore evident that you are at least twenty times more likely to die when pfaffing about in the kitchen, or wherever you keep your toaster: I won’t really judge you on this.

But I am uneasy with this statistic for a number of reasons:

Kitty of the Apocalypse

  1. I have personally never been killed by a toaster and I know how to use one.
  2. Were I in the ocean or aquarium with a large-and-dangerous-enough shark I would feel very self-conscious
  3. A lot of electrocution happens from misuse, rather than an insatiable drive to fulfil an insatiable appetite.
  4. There are a lot more toasters than sharks.
  5. Toasters have only been around for a century or so… Sharks considerably longer.
  6. Proper documentation on shark attacks is a relatively recent thing, giving them a rough 500 millenium headstart on transforming humans into shark noms.
  7. People generally use their toasters more than swim in the ocean.
  8. Toasters don’t really seem that sinister

Point Four interests me particularly. While there are no accurate figures of populations for any shark species (many are endangered or threatened and numbers have generally been declining over the last hundred years) and with great white estimates alone ranging from hundreds to thousands,  I did manage to find some toaster statistics: 15.3 million made in 2006 (an increase of 3.38% from 2005). Apparently toasters also last six to eight years and that means those made in 2006 are probably still around, so this cumulates (with the respective increases) to about 99.9 million toasters in the world. I would say that is a very conservative estimate, as this figure would only provide one toaster for every three people in North America alone.

Admire the interesting avant-garde design.

Anyway, that is all fine and dandy. What about dangerous shark populations? Considering the species depletion and that most sharks need to be adult and over 2 metres to be a general ‘threat’ I can only guess wildly that maybe the number would be somewhere around a million. Probably more, possibly less.

For the purposes of this totally inaccurate and non-scientific study, that means toasters outnumber sharks a hundred to one. Therefore if you matched the toaster and shark populations, both at say 100 million and assumed fatality frequency was proportionate, sharks would then be responsible for 1500 deaths a year; five times that of the toaster.

Of course, this is highly unlikely because if shark attacks were that high I’m sure there’d be a much greater human aversion to being in their environment; causing a corresponding decrease. But you know, that’s logic for you.

“Five times that of your toaster”

Similarly, time spent around/using toasters are subject to debate (Point Seven). Is it unreasonable to say that everyone who has a toaster uses it? However, not everyone has access to shark-infested water (which admittedly, is most water), the ability to swim in it, the time to go to it regularly, and the fundamental desire to go in it. If we assume a toaster is used once a day for 3 minutes (18 hours and 15 minutes a year) you would also have to clock up the same amount of annual risky swimming time for the comparison to be fair, and no, this does NOT mean you can be behind shark nets either, or take other protective measures. You wouldn’t wear insulated gloves and a rubber suit when handling toast now would you? Being in the natural environment is essential! (Though if you do use a fork to get things out of an operating toaster, it might also stand to reason that you should do your swimming in a seal costume and around the RING OF DEATH off Seal Island) Also, you can use your toaster anytime, but in some parts of the world people can only feasibly swim in the summer months, translating around an hour a week in the summery third of the year to offset your toaster-time.

I doubt this is realistic in general; obviously the actual number varies dramatically from person to person as it is often a lifestyle factor. Let’s say the average person spends two hours a year in the ocean (on a suitable equatorial holiday or something): nine times less than required. If there’s a correlation that would mean shark attacks would leap to 136 a year, reaching almost half the toaster-death amount.

Don’t let his playful appearance deceive you!

AND IF WE COMBINE THESE TWO FACTORS….

15 current fatal shark attacks a year x 100 (to equal toaster numbers) x 9 (to equal time around toasters)= 13 500 Deaths per year.

Therefore SHARKS are proportionately FORTY-FIVE (45) times more lethal than toasters

Also bear in mind that these are just the fatal attacks. According to the above sources, fatal attacks are only around 17.6% of documented ‘attacks’ and this would cause 76 500 people to find themselves in some sort of uncomfortable sharky experience. (255 times more likely than their toaster-death scenario)

The moral here is: If you want to compare toasters and sharks and how big a threat they pose to humanity, make sure they exist in similar numbers and we use/annoy them to similar degree.

Moral Fibre.

If comparisons of such statistics are ignored then it is possible to come up with all sorts of obscure or misleading truths that provide both a false sense of security in situations of actual danger, while simultaneously managing to inspire a paranoid approach to everyday activities and objects that becomes the daily sensationalist ambrosia of the trash-media.

That said all the above calculations are scientifically useless. So, you know, ignore them.