[inverse_pi]

There are test tracks. Both Waymo and Uber have publicly said that they have fake cities to test the code https://www.theatlantic.com/technology/archive/2017/08/insid...

http://www.businessinsider.com/ubers-fake-city-pittsburgh-se...

[jay_kyburz]

I guess there are no cyclists crossing the road unexpectedly in Ubers fake city.

Do they have crash test dummy kids running out on the road? To they have road work with giant potholes?

[mcny]

Not that I know too much about machine learning but even in my very limited experience with homework we came across the problem of over fitting: where our model fits the noise of the training data too well but will not perform well against other real world data.

I can't even imagine the amount of data being generated by the fleets at waymo and others but compared to all the infinite possibilities I must assume their data set is tiny.

[inverse_pi]

I can't imagine test tracks data being in the training set, so overfitting is irrelevant here.

[inverse_pi]

> It has a giant roundabout, fake cars, and roaming mannequins that jump out into the street without warning

Well, there you go.