The Presence of Ruin: Why You shouldn’t Drive a Motorbike
The blind spot of statistics
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Suppose you’re interested in a new pill against headaches. You set up a double-blind experiment, get a few thousand participants, separate them into two groups (real pill and placebo) and run the test. Then you analyse the results and of all of the people who didn’t receive a placebo, 60% report their headache gone after the pill.
Now you’re the one having a headache. Is it right to assume that there is a 60% chance this pill would heal your pain?
Yes. And also no.
The problem is that a headache is a broad term and we are complex creatures. Without further testing, we simply don’t know which headaches exactly were healed. You might happen to have the right biology or the right kind of headaches and this pill will work 10/10 times for you. Or perhaps you’re unlucky and this pill will never relieve you from pain.
This example illustrates the problem of dealing with a complex system in a simplistic manner. The results we got from our experiment were 1-dimensional while an individual is a being containing almost infinite variables.
Let’s set up another experiment. This time we are interested in how deadly a motorbike ride can be. We’re not interested in minor or major injuries, only the survivability of motorbike riders.
We find 100 volunteers, and for the sake of the mental experiment let’s assume they are all of the equal height, age, gender (…) and even skill level. Practically clones. We give them all exactly the same bike and send them out on a road for a day.
After the first ride, 99 return alive. The dead rider gets replaced.
We run the experiment again, this time 98 survive. Next time all 100 come back. Then 97. And so on. After many such experiments, we conclude that an average motorbike ride has a 98% survival rate.
Enter the midlife crisis any you decide to buy a motorbike. How would you assess the risk of your new hobby according to the previous experiment?
The first thought is that riding a motorbike has a 2% mortality rate. That might sound a lot or not that much (depending on how much you love to ride), but in any…