[djfix13]

beh qui è detto tutto:
[IMG]https://miro.medium.com/max/765/1*TS2hsRr528UHQG9nDJhIcA.jpeg[/IMG]

Very easily, you will notice that the accuracy for this model is very very high, at 99.9%!! Wow! You have hit the jackpot and holy grail (*scream and run around the room, pumping the fist in the air several times*)!

But….(well you know this is coming right?) what if I mentioned that the positive over here is actually someone who is sick and carrying a virus that can spread very quickly? Or the positive here represent a fraud case? Or the positive here represents terrorist that the model says its a non-terrorist? Well you get the idea. The costs of having a mis-classified actual positive (or false negative) is very high here in these three circumstances that I posed.

OK, so now you realized that accuracy is not the be-all and end-all model metric to use when selecting the best model…now what?