Questions tagged [sgd]
Stochastic Gradient Descent (SGD) is an iterative algorithms used for objective function optimization used in machine learning models.
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Why does SGDRegressor with partial_fit not converge to the same R2 as RidgeCV
I have a dataframe of about 200 features and 1M rows that I can train a RidgeCV model and get an R2 of about 0.01
I'd like to scale up my training to 5M or 10M rows but that won't fit in memory for me ...
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How to calculate gradient of MSE in backpropagation? [duplicate]
I want to implement a neural network from scratch to solve linear regression by using backpropagation. I don't understand how to compute the gradient of the MSE cost function with respect to each ...
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Solving constraint optimization with alternate gradient descent optimization
Problem Setup: Offline contextual bandit with logs of form - <input_context, action, reward>.
Model: A logging/behavior policy $\pi_0$ is used to collect the log data, with context $x_i$, action ...
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SGD for Graph Neural Networks
I was going through some research papers about Graph Neural Networks; what struck me is that very often SGD is used as optimiser (as in PointGNN, DGCNN and Graphsage).
I figured that for "regular&...
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Difference between sklearn's LogisticRegression and SGDClassifier?
What is the difference between sklearn's LogisticRegression classifier and its SGDClassifier? I understand that the SGD is an ...
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Gradient descent vs stochastic gradient descent vs mini-batch gradient descent with respect to working step/example
I am trying to understand the working of gradient descent, stochastic gradient descent and mini-batch gradient descent.
In case of gradient descent, gradient is computed on the entire dataset at each ...
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Understanding SGD for Binary Cross-Entropy loss
I'm trying to describe mathematically how stochastic gradient descent could be used to minimize the binary cross entropy loss.
The typical description of SGD is that I can find online is: $\theta = \...
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How variable alpha changes SGDRegressor behavior for outlier?
I am using SGDRegressor with a constant learning rate and default loss function. I am curious to know how changing the alpha parameter in the function from 0.0001 to 100 will change regressor behavior....
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Understanding Learning Rate in depth
I am trying to understand why the learning rate does not work universally. I have two different data sets and have tested out three learning rates 0.001 ,0.01 and 0.1 . For the first data set, I was ...
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Multiple models have extreme differences during evaluation
My dataset has about 100k entries, 6 features, and the label is simple binary classification (about 65% zeros, 35% ones).
When I train my dataset on different models: random forest, decision tree, ...
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How exactly do you implement SGD with momentum?
I am looking up sources to implement SGD with momentum, but they are giving me different equations.
(beta is the momentum hyper-parameter, ...
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Why does using Gradient descent over Stochatic gradient descent improve performance?
Currently, I'm running two types of logistic regression.
logistic regression with SGD
logistic regression with GD
implemented as follows
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Learning rate of 0 still changes weights in Keras
I just trained a model (SGD) with keras and was wondering why the change of accuracy and loss from epoch to epoch doesn't really decrease that much when I lower the learning rate. So I tested what ...
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Changing the batch size during training
The choice of batch size is in some sense the measure of stochasticity :
On one hand, smaller batch sizes make the gradient descent more stochastic, the SGD can deviate significantly from the exact ...
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input shape of keras Sequential model
i am new to neural networks using keras,
i have the following train samples input shape (150528, 1235) and output shape is (154457, 1235) where 1235 is the training examples,
how to put the input ...
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Problem of multi class classification (Sklearn TfidfVectorizer and SGDClassifier)
I do the (text) topic classification using TfidfVectorizer and SGDClassifier, literally I want to classify the website into categories (like Sport, Business etc).
Now, the problem is, that each ...
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Confused between optimizer and loss function
I always thought the SGD was a loss function then I read this on a notebook
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The central idea behind SGD
Pr. Hinton in his popular course on Coursera refers to the following fact:
Rprop doesn’t really work when we have very large datasets and need to perform mini-batch weights updates. Why it doesn’t ...
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