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by kainolophobia 3172 days ago
>I suggest that dataset bias is real but exaggerated by the tank story, giving a misleading indication of risks from deep learning

I don't see how this story gives a "misleading" view of deep learning. From my (admittedly limited) experience with self-driving RC cars, this type of mistake is quite easy for a neural net to make while being quite difficult to detect. In our case, after utilizing a visual back-prop method, we realized our car was using the lights above to direct itself rather than the lanes on the road.

Now, you can refute this and say "well clearly your data wasn't extensive enough" or "your behavioral model is too simple for a complicated task like driving" however as these tools become easier to use, more and more organizations will put them into practice without as much care as the researchers behind most of the current production efforts.

2 comments

Another more modern and well-documented example of this would seem to occur in a 2015 write-up of the "Right Whale" competition in Kaggle: http://felixlaumon.github.io/2015/01/08/kaggle-right-whale.h...

Contrary to this author's claims, despite using data augmentation and a fancy modern CNN, a neural network trained to identify whales hit a local optimum where it looked at patterns in waves on the water to identify the whale instead of distinctive markings on the whale's body.

I don't buy the "this isn't a problem in real world applications" argument being made in this article.

He says that his first attempt at whale recognition looked at waves instead of whales, but

> This naive approach yielded a validation score of just ~5.8 (logloss, lower the better) which was barely better than a random guess.

which is different from the tank story. For the tanks, the neural network appeared to perform well, but was actually not looking at the tanks. Here, it never performed well, and when debugging why not he found that it was not looking at the whales.

> I don't buy the "this isn't a problem in real world applications" argument being made in this article.

Me neither. Especially considering that this story was already alive before the latest deep learning advances. It is totally believable.

And even with a modern CNN approach, you would expect a model to be able to learn a sunny/cloudy categorization much easier than the nationality of a tank.

This story was repeated by professionals for ages because it is totally believable.

I assume you're referring to some simple lane-keeping CNN where the CNN predicts steering angle from a video recording+human inputs: and yes, your dataset isn't extensive enough, and you'll never have enough data either, not due to some amusing bias in your CNN or taking shortcuts, but because it's a reinforcement learning problem and not a classification problem - your RC CNN could learn a better model of the road which doesn't involve lights at all and it won't make any real difference, it'll still be unable to correct for its errors or adapt to new situations and crash.
I did the human version of this when I was a newbie driver. I learned to predict traffic lights changing to red by watching the pedestrian signals as I approached an intersection. All the lights all over the city followed the same pattern. Then one day I happened upon one where the pattern was different, and I stopped for no reason at a green light, like an idiot.