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Deep Neural Decision Forests [pdf]

research.microsoft.com

31–38 of 38 posts

Re: Deep Neural Decision Forests [pdf]

#31

Earlier quoted context omitted.

New frontier? They've been popular for over 20 years.

That's AI. Every generation invents everything again. Probably works this way in other fields too. (Yes this is hyperbole, but any old timers out there will know the feeling)

> That's AI. Every generation invents everything again.

Also "Past decades was AI winter. But no worries, now we'll start seeing human intelligence in a about next year" probably heard that since late 90's.

Re: Deep Neural Decision Forests [pdf]

#32
post #3
post #2

Could someone explain in layman words what is the qualitative contribution of the paper and why it is important?

Sure. Random forests are a very powerful machine learning method that has proven to give excellent performance with very little tuning. Neural networks with many layers (aka deep learning) is the new frontier of machine learning - they are very powerful but require extensive tuning (the architecture of the network) and lots of examples before they become practical. In this paper, the authors combine the two methods -…

>> One of the main theoretical results in the paper is that they propose a differentiable .. technique to optimize the parameters of the trees.

Yay! Now Decision Trees too can get stuck in local optima! :D

(totally tongue in cheek)

Re: Deep Neural Decision Forests [pdf]

#33

Why do they only compare their method against GoogLeNet? VGG was the winner in 2014, most papers seem to use VGG and my team has observed it to always gets higher accuracy than GoogLeNet.

GoogLeNet "won" ImageNet 2014[1], but VGG is often found to be more flexible.

I'm not entirely sure, but I think that the multiple softmax layers in GoogLeNet might make it easier to modify for this purpose than the VGG architecture.

[1] http://image-net.org/challenges/LSVRC/2014/results (look for "Classification+localization with provided training data: Ordered by classification error")

Re: Deep Neural Decision Forests [pdf]

#34
post #24
post #23

Earlier quoted context omitted.

Deep learning has really only recently become successful with new learning algorithms such as constrastive divergence and convolutional neural networks. Previous efforts were focused around backpropagation, but due to the signal loss across many layers there was never enough information in the output layer to successfully train the network.

Time for a fact update! My, my, how time flies. Deep learning has really only recently become successful hinton coined the term "deep learning" around 2006/2007 (more around deep belief nets/RBMs, but still, same thing), if that's considered "recently." constrastive divergence and convolutional neural networks. CD was also ~10 years ago. CNNs were reading your checks and postal zipcodes in the mid 90s. successfully t…

The 2012 ImageNet results were what really launched the current interest.

Before that there was little evidence that any form of neural network was massively better than other forms of machine learning. Now it has become clear that isn't the case.

Re: Deep Neural Decision Forests [pdf]

#35
post #3

Earlier quoted context omitted.

Sure. Random forests are a very powerful machine learning method that has proven to give excellent performance with very little tuning. Neural networks with many layers (aka deep learning) is the new frontier of machine learning - they are very powerful but require extensive tuning (the architecture of the network) and lots of examples before they become practical. In this paper, the authors combine the two methods -…

>> One of the main theoretical results in the paper is that they propose a differentiable .. technique to optimize the parameters of the trees. Yay! Now Decision Trees too can get stuck in local optima! :D (totally tongue in cheek)

Even though this is tongue-in-cheek, it makes no sense. Decision trees are traditionally trained in a greedy, non-globally-optimal fashion.

Re: Deep Neural Decision Forests [pdf]

#36
post #33

Why do they only compare their method against GoogLeNet? VGG was the winner in 2014, most papers seem to use VGG and my team has observed it to always gets higher accuracy than GoogLeNet.

GoogLeNet "won" ImageNet 2014[1], but VGG is often found to be more flexible. I'm not entirely sure, but I think that the multiple softmax layers in GoogLeNet might make it easier to modify for this purpose than the VGG architecture. [1] http://image-net.org/challenges/LSVRC/2014/results (look for "Classification+localization with provided training data: Ordered by classification error")

Oh that's right, GoogLeNet did edge out VGG in the pure classification task. Localization is essential to us, so VGG was the clear winner for us :)

Re: Deep Neural Decision Forests [pdf]

#37
post #22

Earlier quoted context omitted.

New frontier? They've been popular for over 20 years.

Old time neural networks not even came close to current models in terms of performance. I clearly remember in my machine learning class, one professor mentions neural networks and says it is slow and impossible to tame when the layers goes up thus loses its popularity. That is just 3-4 years ago.

I took some machine learning classes a while 1-2 years ago at the TU Berlin, and while there was some emphasis on neural nets, it was just as much emphasis on SVMs, with the remainder of the time filled with other traditional models. The lecturer had done some research into SVMs, though, so it was probably just bias rather than old-fashionedness. He was also of the mathematical sort, and I suspect the unanalyzable nature of NNs rubbed him the wrong way. I'm not saying that all other AI/ML methods should be abandoned, but NN definitely didn't get the attention it deserved. Deep learning techniques weren't covered at all, for example.

Re: Deep Neural Decision Forests [pdf]

#38

Earlier quoted context omitted.

>> One of the main theoretical results in the paper is that they propose a differentiable .. technique to optimize the parameters of the trees. Yay! Now Decision Trees too can get stuck in local optima! :D (totally tongue in cheek)

Even though this is tongue-in-cheek, it makes no sense. Decision trees are traditionally trained in a greedy, non-globally-optimal fashion.

What I mean is that decision trees are not seen as optimising a function so it doesn't make much sense to think of them as finding optima, or getting stuck in sub-optima (if I may).

That's the traditional view. I guess it's always possible to see decision trees as optimising a binary function, but that's probably to be filed under "original research". Or maybe not- I'm not sure.

In any case, I've never heard of anyone worried that a tree learner would get stuck anywhere. The concern is usually with overfitting.

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