Questions tagged [cost-function]

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Regularization for intercept parameter

Why is the regularization parameter not applied to the intercept parameter? From what I have read about the cost functions for Linear and Logistic regression, the regularization parameter (λ) is ...
2
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0answers
58 views

Neural network cost is constant never changing during training

I am trying to build a binary classifier to predict a pulsar star with Single Hidden layer Neural Network. But the cost on training dataset after almost 100 iterations has no change, following is the ...
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0answers
143 views

How to resolve the instability of average reward per episode in training of DQN (Deep Q-Network)?

what is shown when average reward per episode in training is unstable? If there is big difference between average reward per episode and final reward by test section, what we can say? For ...
2
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0answers
357 views

Cost/loss functions for multi-tasking regression neural networks

The mean square loss function is the standard for regression neural networks. However, if I have a neural network learning two tasks (two outputs) at once, is it more advisable to train on the sum of ...
1
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1answer
30 views

Reason behind the sum of rate factors for calculating cost function derivative

Suppose we have a network of neurons like below: We make a little change in weight w[l][j][k] on our network, and it can make change on our cost function from ...
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0answers
97 views

Minimum cost is not zero when calculating cross-entropy on soft labels

I am training a neural network using batches of soft labels, e.g. y = [[0.00, 0.25, 0.25, 0.50], ... [0.75, 0.00, 0.20, 0.05]] However, as ...
1
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1answer
92 views

How to Define a Cost Fucntion?

I want to define a cost function in python to identify optimum value in days when i should end a marketing campaign to save spend on campaigns not generating traffic good traffic. Problem is I dont ...
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0answers
104 views

How to decrease the learning rate only when cost function is stagnant?

I'm training a very complex function in tensorflow. Is there a way to decrease the learning rate only when the cost isin't decreasing very much?
1
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0answers
215 views

Altered priors for classification trees

I am using the rpart function (in the "rpart" package) in R to fit a cost-sensitive classification tree. I have read the corresponding vignette, which says that misclassication costs are incorporated ...
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0answers
9 views

Simplifying Log Likelihood equation

I am reading through a paper (https://www.mitpressjournals.org/doi/pdf/10.1162/0891201053630273) where they describe logloss as a ranking function and can be simplified to the margin of the training ...
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1answer
24 views

Chain function in backpropagation

I'm reading a Neural Networks Tutorial. In order to answer my question you might have to take a brief look at it. I understand everything until something they declare as "chain function": It's ...
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0answers
8 views

How to design a two-factor optimization score function?

What if I have two parameters as optimization target and want to maximize one and minimize the other one? Example: food products dataset, look for strawberries and artichokes in USDA FDC. Task: find ...
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0answers
17 views

Theano gradient descent and cost function issue

Sorry but can anyone point out whats wrong with this code? ...
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0answers
35 views

Understanding about RNN loss

Problem I am now taking Andrew Ng's deep learning course on Coursera. Everything is great but when it comes to RNN, I sometimes feel confused. Here is a question about RNN (or more specifically, the ...
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1answer
46 views

How to get a rebalance strategy with a cost matrix?

In the case of a classification problem where a cost matrix is used to maximize the model performance, it is common to do a rebalance technique. Let's say for example that I have the following costs ...
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2answers
465 views

Should the cost function be zero using TensorFlow's sigmoid_cross_entropy_with_logits?

I'm building a CNN to make a binary classification (1 or zero). For this, I'm using the cost function sigmoid_cross_entropy_with_logits. But for some reason, the ...