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1500 questions
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3 answers

Data Science oriented dataset/research question for Statistics MSc thesis

I'd like to explore 'data science'. The term seems a little vague to me, but I expect it to require: machine learning (rather than traditional statistics); a large enough dataset that you have to run analyses on clusters. What are some good…
user3279453
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Effect of NOT changing filter weights of CNN during backprop

What is the effect of NOT changing filter weights of a CNN during backpropagation? I changed only the fully connected layer weights while training on the MNIST dataset and still achieved almost 99 percent accuracy.
Abhisek Dash
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What's the difference of stateless LSTM and a normal feed-forward NN?

From what I understand, the whole point of LSTM is for the network to establish long-term dependencies in the data, i.e. an event happening now may be in some way determined by something that happened sometime in the past, and that may not be in the…
BigBadMe
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What is the Time Complexity of Linear Regression?

I am working with linear regression and I would like to know the Time complexity in big-O notation. The cost function of linear regression without an optimisation algorithm (such as Gradient descent) needs to be computed over iterations of the…
user134132523
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7 answers

I got 100% accuracy on my test set,is there something wrong?

I got 100% accuracy on my test set when trained using decision tree algorithm.but only got 85% accuracy on random forest Is there something wrong with my model or is decision tree best suited for the dataset provided. Code: from…
Harigovind Valsakumar
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3 answers

What is the best method for classification of time series data? Should I use LSTM or a different method?

I am trying to classify raw accelerometer data x,y,z to its corresponding label. What is the best architecture for best results? Or, does anyone have any suggestions on LSTM architectures built on keras with input and output nodes?
rosy
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Q-Learning: Target Network vs Double DQN

I am having a hard time understanding difference between Target Network and Double DQN From this blog: Target Network generates the target-Q values that will be used to compute the loss for every action during training. The target network’s weights…
Kari
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Synthetic Gradients good number of Layers & neurons

I would like to train my LSTM with a "synthetic gradients" Decoupled Neural Interface (DNI). How to decide on the number of layers and neurons for my DNI? Searching for them by trial end error or what's worse - by Genetic algorithm which would…
Kari
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5 answers

Share Jupyter Notebook with a non programmer

I would like to share a Jupyter Notebook with somebody who is not a programmer (via a URL). I understand that I must publish my work to GitHub and then use http://nbviewer.jupyter.org/ to render the notebook. However, I don't know how to correctly…
Antonio
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Understanding scipy sparse matrix types

I am trying to select the best scipy sparse matrix type to use in my algorithm. In that, I should initialize data in a vij way, then I should use it to perform matrix vector multiplication. Eventually I have to add rows and cols. Trying to select…
Federico Caccia
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Using RNN (LSTM) for Gesture Recognition System

I'm trying to build a gesture recognition system for classifying ASL (American Sign Language) Gestures, so my input is supposed to be a sequence of frames either from a camera or a video file then it detects the sequence and maps it to it's…
Anas Ezz
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11
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2 answers

Automatically generating images for an art show with deep learning software

My pursuit is to generate something like a grottesque(a kind of painting producing human-animals and plants hybrids). I need to do something like this painting in order to create an art exhibition. I don't need that produced images are ordinate or…
Nico Ghira
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How to estimate GridSearchCV computing time?

If I know the time of a given validation with set values, can I estimate the time GridSearchCV will take for n values I want to cross-validate?
Nathan Furnal
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PySpark dataframe repartition

What happens when we do repartition on a PySpark dataframe based on the column. For example dataframe.repartition('id') Does this moves the data with the similar 'id' to the same partition? How does the spark.sql.shuffle.partitions value affect the…
Nikhil Baby
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What is the use of additional column of 1s in normal equation?

Currently I am going through Normal Equation in Machine Learning. $$ \hat\theta = (X^T \cdot X)^{-1} \cdot X^T \cdot y $$ But when I see how they use this equation, I found they always add an additional column of 1s in the starting of matrix X…
Sreeraj Chundayil
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