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Show HN: Neural Network Visualizer Classifying Handwriting – D3/Redux

nn-mnist.sennabaum.com

11–20 of 20 posts

Re: Show HN: Neural Network Visualizer Classifying Handwriting – D3/Redux

#11
> Most networks gained a large percentage of their final accuracy in just one epoch. And it usually was the case that a higher accuracy in the first epoch meant a higher final accuracy.

This sounds to me like learning was just crawling to local optimum not actually exploring or making any breakthrough in understanding of the domain.

Re: Show HN: Neural Network Visualizer Classifying Handwriting – D3/Redux

#12

Just a note: Logistic regression on raw pixels already gets you 88% accuracy. Nearest-neighbors on raw pixels gets you 95% accuracy. You should not draw too much conclusion from a network with accuracy < 97%, because you probably just have bad hyperparameters (except for conclusions about which hyperparameters you need to tune).

do you have a source for these? ta

Re: Show HN: Neural Network Visualizer Classifying Handwriting – D3/Redux

#13

Just a note: Logistic regression on raw pixels already gets you 88% accuracy. Nearest-neighbors on raw pixels gets you 95% accuracy. You should not draw too much conclusion from a network with accuracy < 97%, because you probably just have bad hyperparameters (except for conclusions about which hyperparameters you need to tune).

do you have a source for these? ta

https://www.google.com/#q=mnist

Re: Show HN: Neural Network Visualizer Classifying Handwriting – D3/Redux

#14
post #7
post #6

Earlier quoted context omitted.

If possible, send it off to a web worker? That free's up the UI thread Edit: So it's the rendering that's hard on the CPU. Canvas would probably improve performance. Also, the graphic is so simple and there doesn't seem to be any event listeners on the edges themselves, that converting should be trivial :)

Hmm, that sounds like a promising idea...

For the most part you're not doing live animations, statically drawing on a 3 canvases would give you what you want (without huge overhead of DOM nodes and simplicity of 2D canvas painting). Web workers aren't going to do much since most of your lag is coming from way too much DOM (causing layout, repaints to take forever).

Re: Show HN: Neural Network Visualizer Classifying Handwriting – D3/Redux

#15

Too slow; didn't wait to load. Has anyone tried training a neural network on anything that isn't the NIST digits? I've seen that one so done to death and a dearth of other examples that I'm starting to get skeptical that it would work on any other cases. Or is it that the data is expensive and the data "scientist" is cheap?

I basically only see to-do list apps for new frameworks. So therefore frameworks can only make to-do lists.

Re: Show HN: Neural Network Visualizer Classifying Handwriting – D3/Redux

#16
post #15

Too slow; didn't wait to load. Has anyone tried training a neural network on anything that isn't the NIST digits? I've seen that one so done to death and a dearth of other examples that I'm starting to get skeptical that it would work on any other cases. Or is it that the data is expensive and the data "scientist" is cheap?

I basically only see to-do list apps for new frameworks. So therefore frameworks can only make to-do lists.

Clever, hah - also loving your equally clever username.

Re: Show HN: Neural Network Visualizer Classifying Handwriting – D3/Redux

#18

Can anyone explain how the "floats" that are the output of the last layer correspond to the individual digits?

The largest float in the output layer (while the graph is yellow) is the activation. The largest activation in the final layer is the network's "guess". The guess is the index of the last layer, which corresponds to a particular digit.

Re: Show HN: Neural Network Visualizer Classifying Handwriting – D3/Redux

#19
post #18

Can anyone explain how the "floats" that are the output of the last layer correspond to the individual digits?

The largest float in the output layer (while the graph is yellow) is the activation. The largest activation in the final layer is the network's "guess". The guess is the index of the last layer, which corresponds to a particular digit.

Awesome, I just flipped that switch at the top and can see how it calculates the individual handwritten inputs. Great demo!

So I guess during training you're telling it that correct answers should be 1 and the incorrect answers should be 0.

Do the encoding choices that you make regarding the input / output of a neural network influence its performance at all? Maybe for MNIST the way you have it is the most common approach?

Re: Show HN: Neural Network Visualizer Classifying Handwriting – D3/Redux

#20
post #18

Earlier quoted context omitted.

The largest float in the output layer (while the graph is yellow) is the activation. The largest activation in the final layer is the network's "guess". The guess is the index of the last layer, which corresponds to a particular digit.

Awesome, I just flipped that switch at the top and can see how it calculates the individual handwritten inputs. Great demo! So I guess during training you're telling it that correct answers should be 1 and the incorrect answers should be 0. Do the encoding choices that you make regarding the input / output of a neural network influence its performance at all? Maybe for MNIST the way you have it is the most common app…

Usually the number of nodes in the input and output layers don't affect things all that much. They are relatively set based on the problem. The number of nodes in the hidden layers, the number of hidden layers, and various other parameters such as cost and activation functions, are mostly what you use to tune performance.
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