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When my wife heard the stories of shark attacks this year, she immediately became concerned for our safety, and wondered if we should cancel our trip to the beach.

With that as my perspective, here are my counterpoints:

1. 'Almost everyone takes selfies but many, many fewer of us are exposed to shark attacks.'

True, but there are a huge number of people who swim in the ocean. So the comparison is not so unfair as you make it out to be.

2. 'it misleads readers into thinking that selfies are more dangerous.'

Perhaps it is more dangerous. The question is not, 'is it more dangerous to take a selfie or swim with sharks?'. Rather, the question is this: 'is it more dangerous to take a selfie or to swim in the ocean?'

3. 'your risk of dying from selfies is ridiculously low'.

Your risk of dying from a shark attack when swimming in the ocean is also ridiculously low.


Tim: Think magnitude, not just direction.


My immediate take on it is about how we assess the risk. I live in Australia and whenever we get visitors they seem to think that if they swim in the sea it is very likely they will be attacked by a shark. However the idea that a selfie will kill you does not even enter into many peple's minds.

So is it misleading to suggest that we underestimate the selfie as a threat, albeit one that comes from just not paying attention to what you are doing.

Getting a realistic idea of the two threats seems improbable, but moving people from complete certainty or complete uncertainty might have some merit.


We had a photobombing shark http://www.smh.com.au/nsw/photobombing-shark-at-bondi-a-bit-fishy-photographer-says-20150924-gju5ll.html but it seems to be a fake.


technically, sharks don't kill people. people die from blood loss. so if you're going to call people out for getting on top of moving vehicles as the culprit, then you need to call it across the board.

Using your logic of percentage statistics, no that many people are killed each year by prescriptions drugs as there are MILLIONS of people on prescription drugs.

if your head is in the oven, and your feet are in ice water - don't worry. your temperature is pretty average.


Sketch: When you have an app to disable the self-facing camera on smartphones, please do give us a link to save some lives. In the meantime, mind your numerators and denominators.

Tom H.

Google released some stats last year: 93 million selfies taken on the Android platform. Roughly double that for the total number of selfies (Android is about 50% of the market).

So we have about 1 death every 4 billion selfies.

There were 3 fatalities from unprovoked shark attacks last year, and 72 unprovoked attacks, or 1 death every 24 attacks. Personally, I agree with Tim's point that we should be comparing time at the beach to selfies, rather than shark attacks. The shark attack is more like the fall that happens when you're taking a selfie, which can't be either predicted or controlled and might end up being fatal.

Very hard to estimate the time spent world-wide each year at the beach, but it may be a few billion person-hours, giving us roughly 1 death from unprovoked shark attack per billion person-hours at the beach.

So shark attacks and taking selfies are probably similar risk levels. Both are so small as to be negligible.

Thanks for keeping our heads in the numbers, Kaiser.


Tom H.: Point taken. We need a better measure of the base population: limit to those who are truly exposing themselves to the risk. In the case of selfies, they are people acting dangerously (like taking selfies on top of a moving train); in the case of beaches, it is people who spend significant time in shark-infested waters.

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Kaiser Fung. Business analytics and data visualization expert. Author and Speaker.
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