Security Awareness Blog

Judging Risk - Sharks versus the Vending Machine

One of the things I like to cover in my Securing The Human talks is how bad we humans are at judging risk. What may have worked for us 100,000 years ago in the grass plains of Africa no longer works in the 21st century. Risks back then were the type of risks that ate us, however risks now a days are far more complex. One of the problems is we greatly over estimate risks that we should not, and underestimate the real risks. One of my favorite examples is to ask people what greatest things they are afraid of when they visit the ocean? One of the most common things I hear are sharks, or more precisley being eaten by a shark while swimming in the ocean. Now this is a pretty scary thought, I personally do not like the idea either. However the odds of being eaten by a shark are 1 in 251,800,000. You probably have better luck with the lottery. Now, think about something else that can kill you while you visit the beach. In fact something twice as likely, what would it be? Vending machines. Yup, you have that correctly, vending machines are twice as likely to kill you as a shark. Think about it. People put their money in the vending machine but the bottle of coke does not come out. So they start shaking and rocking the machine to get their drink. It ends up falling on them and killing them.

I'm bringing this up because I just read an interesting article on A frustrated reporter was writing about his experience with broken vending machines, then has a survey asking his readers what is their most common response is when a vending machine does not give them their product. Out of nine different choices, the number one choice was ..... you guessed it shaking the machine. Of the 25,000 repondents, over 45% said they rock the machine. Little do these people realize it would probably be safer to pet a shark.


Posted September 15, 2010 at 8:36 PM | Permalink | Reply


Nice post, Lance.
Now, unfortunately, getting some kind of qualitative and quantitative appreciation of the statistics is also hard when given the kind of numbers we are bombarded with everyday. The gut feeling is that being killed by a shark is ''worse' than being killed by a vending machine. Remember that movie where that psychotic vending machine killed all those beach goers in a frenzied manner? Nope, me neither. When I was five, I thought sharks could come up the plug hole of my bath(after watching Jaws). Our understanding of risk does not seem to mature.
Read Dan Gardner's book if you get a chance. Bruce Schneier posted a link to a survey carried out on parents, regarding the same issue.

Posted September 19, 2010 at 9:53 AM | Permalink | Reply


Great points, please keep up the tremendous feedback!

Posted September 15, 2010 at 10:21 PM | Permalink | Reply


Had to chime in again because I've been mulling over the usage of stats to infer the likelihood of things happening in the future. I know that the whole of the actuarial ''science' is based on this kind of thinking but''
I began wondering whether the fact that something happened x many times to x many people in the past means that we can reliably or even realistically project what the chances are of it happening in the future using those historical figures.
Shark attacks for instance. I live in a country where the incidence of shark attacks has risen in certain areas but dropped in others and sometimes has risen in certain months. The nuance and fuzziness of these changes can be explained by greater numbers of people swimming or sharks fleeing fishermen or looking for food closer to the coast etc. So when we say, "You are twice as likely to die from a vending machine falling on you than from a shark attack," the statement needs qualifying, perhaps.
The guy on his sweet malibu who has just seen a grey nurse streaking towards him is probably thinking, "I'm more likely to die from this shark attack then I am from trying to extricate a can of coke from the machine at the surf club later,"
Someone who never goes to the beach or to aquaraiums will never be killed by a shark. Someone who lives at sea, 24/7 will never be killed by a vending machine. I know we're talking averages but they don't make sense to me.
''AIr travel is one of the safest forms of mass transit,' is another favourite. ''Except if you crash, of course,' is my usual response.
Hope that makes sense. I'm just thinking out loud here and wondering if stats and probabilities actually mean what we think they do''after all, we do not live in a Monte Carlo world (especially on Wall Street).