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Why a restricted Boltzman machine (RBM) tends to learn very similar weights?

These are 4 different weight matrices that I got after training a restricted Boltzman machine (RBM) with ~4k visible units and only 96 hidden units/weight vectors. As you can see, weights are extremely similar - even black pixels on the face are…
ffriend
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How to select particular column in Spark(pyspark)?

testPassengerId = test.select('PassengerId').map(lambda x: x.PassengerId) I want to select PassengerId column and make RDD of it. But .select is not working. It says 'RDD' object has no attribute 'select'
dsl1990
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Coreference Resolution for German Texts

Does anyone know a libarary for performing coreference resolution on German texts? As far as I know, OpenNLP and Stanford NLP are not able to perform coreference resolution for German Texts. The only tool that I know is CorZu which is a python…
Pasmod Turing
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Where exactly does $\geq 1$ come from in SVMs optimization problem constraint?

I've understood that SVMs are binary, linear classifiers (without the kernel trick). They have training data $(x_i, y_i)$ where $x_i$ is a vector and $y_i \in \{-1, 1\}$ is the class. As they are binary, linear classifiers the task is to find a…
Martin Thoma
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2 answers

Machine Learning: Single input to variable number of outputs

Is there a machine learning algorithm that maps a single input to an output list of variable length? If so, are there any implementations of the algorithm for public use? If not, what do you recommend as a workaround? In my case, the input is a…
ricksmt
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Recognition human in images through HOG descriptor and SVM classifier performs poorly

I'm using a HOG descriptor, coupled with a SVM classifier, to recognise humans in pictures. I'm using the Python wrappers for OpenCV. I've used the excellent tutorial at pymagesearch, which explains what the algorithm does and furnishes hints on how…
martina.physics
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Keras EarlyStopping callback: Why would I ever set restore_best_weights=False?

The point of EarlyStopping is to stop training at a point where validation loss (or some other metric) does not improve. If I have set EarlyStopping(patience=10, restore_best_weights=False), Keras will return the model trained for 10 extra epochs…
codeananda
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Why is finite precision a problem in machine learning?

Can you explain what is finite precision? Why is finite precision a problem in machine learning?
GeorgeOfTheRF
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Pylearn2 vs TensorFlow

I am about to dive into a long NN research project and wanted a push in the direction of Pylearn2 or TensorFlow? As of Dec 2015 has the community started to lean one direction or another? This link has given me concern about getting tied to…
user3155053
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Best way to search for a similar document given the ngram

I have a database of about 200 documents who's ngrams I have extracted. I want to find the document in my database that is most similar to a query document. In otherwords, I want to find the document in the database that shares the most number of…
okebz
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What is the difference between Trax and Tensorflow?

What is the main difference between Trax and Tensorflow? Both of them are deep learning libraries and implemented by Google. https://github.com/google/trax https://github.com/tensorflow/tensorflow
Bala venkatesh
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Why is deep learning used in recommender systems?

I am currently reading a lot about recommender systems (RS) and came across that many RS are based on deep learning. However, I never find a good scientific article why deep learning is used in RS and why it is more successful compared to other…
Ella
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R error using package tm (text-mining)

I am attempting to use the tm package to convert a vector of text strings to a corpus element. My code looks something like this Corpus(d1$Yes) where d1$Yes is a factor with 124 levels, each containing a text string. For example, d1$Yes[246] = "So…
Ivoire
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How do I encode the categorical columns if there are more than 15 unique values?

I'm trying to use this data to make a data analysis report using regression. Since regression only allows for numerical types, I then need to encode the categorical data. However, most of these have more than 15 unique values such as country. Do I…
Cinemato
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3 answers

Which algorithms or methods can be used to detect an outlier from this data set?

Suppose I have a data set : Amount of money (100, 50, 150, 200, 35, 60 ,50, 20, 500). I have Googled the web looking for techniques that can be used to find a possible outlier in this data set but I ended up confused. My question is: Which…
CN1002
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