Jan 18, 2014

Type vs Type

Type 1 Error = False Positive

Type 2 Error = False Negative

(paraphrasing Michael Shermer)
You're a hominid out for a stroll on the African plains 2 million years ago, and you hear a rustle in the grass.  Do you assume it's a dangerous predator, or do you assume it's harmless?

If you identify the sound as a predator, and it turns out to be the wind, then you've made a mistake (a Type 1 Error).  You lose some time, but you've survived - you continue to hunt and to live and to breed.

If you identify the sound as the wind, but it turns out to be a leopard, then you've removed yourself and all your potential descendants from the gene pool.

We are descended from a very long line of creatures who consistently made Type 1 Errors.

And that (partly) explains why we insist on believing in ghosts; and that Elvis is alive; and that there is a god.

Dr Shermer, if you please:

No comments:

Post a Comment