Questions tagged [backpropagation]

Backpropagation is a method of the gradient computation, often used in artificial neural networks to perform gradient descent.

Backpropagation is a method of the gradient computation, often used in artificial neural networks to perform gradient descent. It led to a “renaissance” in the field of artificial neural network research.

In most cases, it requires a teacher that knows, or can calculate, the desired output for any input in the training set. The term is an abbreviation for "backward propagation of errors".

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The concept of straight through estimator (STE)

I have seen straight through estimator (STE) in many Neural Network related papers e.g. this and this. But I cannot understand the concept. I wonder if anyone could explain STE or refer me to a simple resource?
Amir
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Neural network in Javascript not learning properly

I've tried to rewrite neural network found here to javascript. My javascript code looks like this. function NeuralFactor(weight) { var self = this; this.weight = weight; this.delta = 0; } function Sigmoid(value) { return 1 / (1 +…
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Difference between autograd.grad and autograd.backward?

Suppose I have my custom loss function and I want to fit the solution of some differential equation with help of my neural network. So in each forward pass, I am calculating the output of my neural net and then calculating the loss by taking the MSE…
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PyTorch : predict single example

Following the example from: https://github.com/jcjohnson/pytorch-examples This code trains successfully: # Code in file tensor/two_layer_net_tensor.py import torch device = torch.device('cpu') # device = torch.device('cuda') # Uncomment this to…
blue-sky
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Debugging a Neural Network

TLDR I have been trying to fit a simple neural network on MNIST, and it works for a small debugging setup, but when I bring it over to a subset of MNIST, it trains super fast and the gradient is close to 0 very quickly, but then it outputs the same…
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LSTM RNN Backpropagation

Could someone give a clear explanation of backpropagation for LSTM RNNs? This is the type structure I am working with. My question is not posed at what is back propagation, I understand it is a reverse order method of calculating the error of the…
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Training feedforward neural network for OCR

Currently I'm learning about neural networks and I'm trying to create an application that can be trained to recognize handwritten characters. For this problem I use a feed-forward neural network and it seems to work when I train it to recognize 1,…
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How does a back-propagation training algorithm work?

I've been trying to learn how back-propagation works with neural networks, but yet to find a good explanation from a less technical aspect. How does back-propagation work? How does it learn from a training dataset provided? I will have to code…
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ND Convolution Backprogation

For my education, I am trying to implement an N-dimensional convolutional layer in a convolutional neural network. I would like to implement a backpropagation function. However, I am not sure of the most efficient way of doing so. At present, I am…
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Are there alternatives to backpropagation?

I know a neural network can be trained using gradient descent and I understand how it works. Recently, I stumbled upon other training algorithms: conjugate gradient and quasi-Newton algorithms. I tried to understand how they work but the only good…
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How to build a multiple input graph with tensor flow?

Is it possible to define a TensorFlow graph with more than one input? For instance, I want to give the graph two images and one text, each one is processed by a bunch of layers with a fc layer at the end. Then there is a node that computes a loss…
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Updating weights in backpropagation algorithm

I think I've understood each step of backpropagation algorithm but the most important one. How do weights get updated? Like at the end of this tutorial? http://home.agh.edu.pl/~vlsi/AI/backp_t_en/backprop.html
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Backpropagation algorithm through cross-channel local response normalization (LRN) layer

I am working on replicating a neural network. I'm trying to get an understanding of how the standard layer types work. In particular, I'm having trouble finding a description anywhere of how cross-channel normalisation layers behave on the…
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Weather forecast using a neural network

I am trying to write a program for weather forecasting using backpropagation. I am a beginner in this field. I have historical data with different parameters like temperature, humidity, wind speed, rainfall etc. I am confused about how to provide…
amey
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Neural Network learning rate and batch weight update

I have programmed a Neural Network in Java and am now working on the back-propagation algorithm. I've read that batch updates of the weights will cause a more stable gradient search instead of a online weight update. As a test I've created a time…
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