*Simple statistics show that I learn more from my mistakes, yet I only get rewarded for success. blog.mindrocketnow.com*

Suppose a test for Mind
Rockets is 99% sensitive and 99% specific. That is, the test will produce 99%
true positive results for Mind Rockets and 99% true negative results for
non-Mind Rockets. Suppose that only 0.5% of people are actually Mind Rockets.
If a randomly selected individual tests positive, what is the probability he or
she is a Mind Rocket?

Despite the apparent accuracy
of the test, if an individual tests positive, it is twice as likely that they
are not actually positive, than they are. This surprising result arises because
the number of non-Mind Rockets is very large compared to the number of Mind
Rockets, so a small percentage of a large number is still larger than a large
percentage of a small number.

To use concrete numbers: if
1000 individuals are tested, there are expected to be 995 non-Mind Rockets and
5 Mind Rockets. From the 995 non-Mind Rockets, 9.95 false positives are
expected. From the 5 Mind Rockets, 4.95 true positives are expected. So in our
sample of 1000, out of 14.9 expected positive results, only 4.95 (33.2%) are
genuine.

If we flip this around, out of
the 995 non-Mind Rockets, we expect to find 985.05 true negatives. And in the 5
Mind Rockets, we expect to find 0.05 false negatives. Therefore out of the
sample of 1000, we can expect to find 985.1 negatives, of which 99.99% are
genuine. So we learn more from the negative results than from the positive
results.

Why is this important? As The
Economist pointed out, academic research, particularly pharmaceutical
research, disproportionately rewards positive results, despite negative results
(and even replicating results) being more meaningful. Moreover, society in
general rewards success and doesn’t acknowledge the positives in failure.

I can see that this is
changing in the school where I am a Governor; we’re trying very hard to
“scaffold” the learning so that the children learn through failure as well as
success. But after that, further schooling and then work is still all about
high marks in SATs and performance-based bonuses, and is at odds with personal
growth.

We need our education system
to be more entrepreneurial. I don’t mean that we need all of our students to be
dot com millionaires or winners of the Dyson prize. We need our education
system to give our children the confidence to treat both imposters of triumph
and disaster the same. Because that’s the only way that they will be able to
fill each unforgiving minute with sixty seconds worth of distance run.

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