Questions tagged [machine-learning]

Implementation questions about machine learning algorithms. General questions about machine learning (concepts, theory, methodology, terminology, etc.) should be posted to their specific communities.

Machine learning revolves around developing self-learning computer algorithms that function by virtue of discovering patterns in data and making intelligent decisions based on such patterns.

Machine learning is a subfield of computer science that evolved from the study of pattern recognition and computational learning theory in artificial intelligence. Machine learning explores the construction and study of algorithms that can learn from and make predictions about data. Such algorithms operate by building a model from example inputs in order to make data-driven predictions or decisions rather than following strictly static program instructions.

NOTE: If you want to use this tag for a question not directly concerning implementation, then consider posting on Cross Validated, Data Science, or Artificial Intelligence instead; otherwise you're probably off-topic. Please choose one site only and do not cross-post to more than one - see Is cross-posting a question on multiple Stack Exchange sites permitted if the question is on-topic for each site? (tl;dr: no).

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Does it make sense to use Conda + Poetry?

Does it make sense to use Conda + Poetry for a Machine Learning project? Allow me to share my (novice) understanding and please correct or enlighten me: As far as I understand, Conda and Poetry have different purposes but are largely…
Seub
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How does Apple find dates, times and addresses in emails?

In the iOS email client, when an email contains a date, time or location, the text becomes a hyperlink and it is possible to create an appointment or look at a map simply by tapping the link. It not only works for emails in English, but in other…
Martin
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Google Colaboratory: misleading information about its GPU (only 5% RAM available to some users)

update: this question is related to Google Colab's "Notebook settings: Hardware accelerator: GPU". This question was written before the "TPU" option was added. Reading multiple excited announcements about Google Colaboratory providing free Tesla K80…
stason
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Why does one hot encoding improve machine learning performance?

I have noticed that when One Hot encoding is used on a particular data set (a matrix) and used as training data for learning algorithms, it gives significantly better results with respect to prediction accuracy, compared to using the original matrix…
maheshakya
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TensorFlow, "'module' object has no attribute 'placeholder'"

I've been trying to use tensorflow for two days now installing and reinstalling it over and over again in python2.7 and 3.4. No matter what I do, I get this error message when trying to use tensorflow.placeholder() It's very boilerplate code: tf_in…
user3023715
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What is the difference between a feature and a label?

I'm following a tutorial about machine learning basics and there is mentioned that something can be a feature or a label. From what I know, a feature is a property of data that is being used. I can't figure out what the label is, I know the meaning…
Wojtek Wencel
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Why should weights of Neural Networks be initialized to random numbers?

I am trying to build a neural network from scratch. Across all AI literature there is a consensus that weights should be initialized to random numbers in order for the network to converge faster. But why are neural networks initial weights…
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machine learning libraries in C#

Are there any machine learning libraries in C#? I'm after something like WEKA. Thank you.
Dervin Thunk
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Common causes of nans during training of neural networks

I've noticed that a frequent occurrence during training is NANs being introduced. Often times it seems to be introduced by weights in inner-product/fully-connected or convolution layers blowing up. Is this occurring because the gradient computation…
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How to load a model from an HDF5 file in Keras?

How to load a model from an HDF5 file in Keras? What I tried: model = Sequential() model.add(Dense(64, input_dim=14, init='uniform')) model.add(LeakyReLU(alpha=0.3)) model.add(BatchNormalization(epsilon=1e-06, mode=0, momentum=0.9,…
pr338
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Understanding min_df and max_df in scikit CountVectorizer

I have five text files that I input to a CountVectorizer. When specifying min_df and max_df to the CountVectorizer instance what does the min/max document frequency exactly mean? Is it the frequency of a word in its particular text file or is it the…
moeabdol
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Can Keras with Tensorflow backend be forced to use CPU or GPU at will?

I have Keras installed with the Tensorflow backend and CUDA. I'd like to sometimes on demand force Keras to use CPU. Can this be done without say installing a separate CPU-only Tensorflow in a virtual environment? If so how? If the backend were…
mikal94305
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What is an intuitive explanation of the Expectation Maximization technique?

Expectation Maximization (EM) is a kind of probabilistic method to classify data. Please correct me if I am wrong if it is not a classifier. What is an intuitive explanation of this EM technique? What is expectation here and what is being…
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How to concatenate two layers in keras?

I have an example of a neural network with two layers. The first layer takes two arguments and has one output. The second should take one argument as result of the first layer and one additional argument. It should looks like this: x1 x2 x3 \ / …
rdo
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Scikit-learn: How to obtain True Positive, True Negative, False Positive and False Negative

My problem: I have a dataset which is a large JSON file. I read it and store it in the trainList variable. Next, I pre-process it - in order to be able to work with it. Once I have done that I start the classification: I use the kfold cross…