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11 votes
2 answers
2k views

ggvis vs. ggplot2+Shiny; which one to choose for interactive visualization?

There is a similar question here in CrossValidated, and I have read the answers. My question is a bit different. I don't want to merely visualize my data, and indeed what I want to visualize is not ...
Shahin's user avatar
  • 271
2 votes
0 answers
223 views

Non-linear data preprocessing before mini-batch gradient descent

I found some realisation of pretty interesting ML algorithm. https://github.com/EderSantana/DeepEEG We have dataset X, matrix of spacial filter W, matrix of time filter V, and matrices U and B - ...
user3271237's user avatar
3 votes
1 answer
152 views

How should I convert Logistic Regression's coefs into action strategy?

I am trying to analyze soccer's data set: ...
SpanishBoy's user avatar
2 votes
3 answers
4k views

What is the best file format to store an uncompressed 2D matrix?

For what it's worth my particular case is a symmetrical matrix, but this question should be answered more generally.
Austin Capobianco's user avatar
3 votes
1 answer
3k views

ARIMAX with spark-timeseries

Cloudera recently added the spark-time series library to github. According to the user docs, it definitely can fit autoregressive integrated moving average (ARIMA) models, but I see no mention of ...
Kyle.'s user avatar
  • 1,483
1 vote
1 answer
531 views

What are prototypes in RBF networks?

I am currently reading Boosting the Performance of RBF Networks with Dynamic Decay Adjustment by Michael R. Berthold and Jay Diamond (online) to understand how Dynamic Decay Adjustment (DDA; a ...
Martin Thoma's user avatar
  • 18.9k
13 votes
3 answers
30k views

What is the difference between NLP and text mining?

As discussed with Sean in this Meta post, I thought it would be nice to have a question which can help people who were confused like me, to know about the differences between text mining and NLP! So, ...
Dawny33's user avatar
  • 8,296
3 votes
1 answer
1k views

Tensorflow RNN: Batching data of different length

I'm starting to experiment with neural networks in Google's tensorflow framework, and in particular am working on a model that has an LSTM layer. I am using the RNN tutorial to get me started. To ...
pythonic metaphor's user avatar
3 votes
1 answer
4k views

Classification using xgboost - predictions

I was trying to build a 0-1 classifier using xgboost R package. My question is how predictions are made? For example in random forests, trees "vote" against each option and the final prediction is ...
user2280549's user avatar
0 votes
1 answer
8k views

How can I read in a .csv file with special characters in it in pandas?

I am trying to read in a .csv file containing some data. I only need to read in specific chunks of rows from the file, such as line 15- line 20, line 45-line 50, and so on. However, the file contains ...
user62198's user avatar
  • 1,091
10 votes
1 answer
4k views

Convergence in Hartigan-Wong k-means method and other algorithms

I have been trying to understand the different k-means clustering algorithms mainly that are implemented in the stats package of the ...
Sid's user avatar
  • 101
1 vote
0 answers
315 views

Unbalanced data fit in gbm

I'm trying to build a model using GBM in r in order to get probability of two classes ( 'yes','no'). My data are unbalanced, and because of this I trained my model using a balanced data(undersampling ...
Michael Elma's user avatar
2 votes
0 answers
237 views

Contrastive divergence in RBM

I have the following code, where x in the input data, w is the weight matrix, bv and bh are the biases for the visible and hidden units. ...
user's user avatar
  • 1,993
0 votes
1 answer
2k views

sklearn.naive_bayes VS categorical variables

In a binary classification, how can I use sklearn.naive_bayes python module to predict the class of inputs with 5 categorical variables (not binary)?
innovIsmail's user avatar
2 votes
0 answers
35 views

How to estimate the lambda e to reweighing translation probabilities of entries in a dictionary

In this paper, Brown et al. proposed the usage of dictionary entries in addition to the machine translation probabilities that we're used to in the Math of Statistical Machine Translation. He ...
alvas's user avatar
  • 2,410
5 votes
3 answers
347 views

For every Bayesian Network, is there a Neural Network that gives the same output?

After thinking about a question comparing Bayesian Network to Neural Network, I am now wondering if they may not be one and the same thing! At this point, my maths (unused for over 20 years fails me!)...
Ian Ringrose's user avatar
60 votes
5 answers
54k views

Neural networks: which cost function to use?

I am using TensorFlow for experiments mainly with neural networks. Although I have done quite some experiments (XOR-Problem, MNIST, some Regression stuff, ...) now, I struggle with choosing the "...
daniel451's user avatar
  • 723
1 vote
0 answers
712 views

How to implement a BiLSTM to classify speech data

I would like to know how should I provide the inputs to a BiLSTM if I am going to classify speech files (.wav) files. What is the proper way to label the data? Do I have to label each individual frame ...
udani's user avatar
  • 111
9 votes
4 answers
15k views

How to combine PCA and MCA on mixed data?

Suppose I have mixed data and (python) code which is capable of doing PCA (principal component analysis) on continuous predictors and MCA (multiple correspondence analysis) on nominal predictors. Is ...
Wojciech J. Migda's user avatar
4 votes
1 answer
172 views

What regressors are recommended with text modeling?

For the sake of my own exploration, I am working on a sales prediction project. I am using text extracted from a set of books to build a predictive model. With scikit learn, I have created a Tfidf, ...
Monica Heddneck's user avatar
5 votes
2 answers
281 views

Any case studies using Bayesian Networks for system design trades?

I am exploring using Bayesian Networks to identify the best parameters within a system design, to improve its performance. I'm trying to find any case studies where this has been used successfully or ...
KnotMoving's user avatar
68 votes
6 answers
82k views

What is the Q function and what is the V function in reinforcement learning?

It seems to me that the $V$ function can be easily expressed by the $Q$ function and thus the $V$ function seems to be superfluous to me. However, I'm new to reinforcement learning so I guess I got ...
Martin Thoma's user avatar
  • 18.9k
2 votes
2 answers
192 views

Is there an appropriate sequence of parameters to be considered when building a pipeline in Scikit learn?

DISCLAIMER: I understand this could be considered a subjective type of question, but I'm hoping it is specific enough to not be flagged. Please give it a chance. I am doing a GridSearch in scikit-...
tumultous_rooster's user avatar
7 votes
1 answer
5k views

Can we compare a word2vec vector with a doc2vec vector?

I have set of categories and I want to compare a document vector with word vector of categories to find best matching category. Is it possible to compare a word vector with document vector? If yes, ...
SHASHANK GUPTA's user avatar
21 votes
4 answers
22k views

Hyperparameter search for LSTM-RNN using Keras (Python)

From Keras RNN Tutorial: "RNNs are tricky. Choice of batch size is important, choice of loss and optimizer is critical, etc. Some configurations won't converge." So this is more a general question ...
wacax's user avatar
  • 3,390
17 votes
5 answers
26k views

Number of epochs in Gensim Word2Vec implementation

There's an iter parameter in the gensim Word2Vec implementation ...
alvas's user avatar
  • 2,410
60 votes
9 answers
17k views

Is there any domain where Bayesian Networks outperform neural networks?

Neural networks get top results in Computer Vision tasks (see MNIST, ILSVRC, Kaggle Galaxy Challenge). They seem to outperform every other approach in Computer Vision. But there are also other tasks: ...
Martin Thoma's user avatar
  • 18.9k
0 votes
2 answers
91 views

How to define a suitbale number of centroids for fuzzy c-means?

In Fuzzy c-means, we have to put how many centers(centroids) in the code. I am wondering how many centroids are suitbale ? How to define a suitbale number of centroids for fuzzy c-means?
kgk's user avatar
  • 111
1 vote
1 answer
774 views

Face Recognition using Eigenfaces and SVM

I am new to machine learning. I want to develop a face recognition system using scikit-learn. This is the example given in the tutorials of scikit-learn. I am not getting how the input is being ...
enterML's user avatar
  • 3,031
2 votes
0 answers
199 views

Natural Language text categorization using RapidMiner

I'm new to data mining, so this might sound like a very simple task to some. I work in reliability engineering in aviation and have a set of data that is generated on a daily basis regarding system ...
Yousif Jawhar's user avatar
2 votes
3 answers
222 views

Clustering weekly data to detect outbreaks by having some sort of continuity among the adjacent weeks

I have a dataset from some health institues. The data contains information about malaria cases on a 52 week range. The dataset has 52 columns, one for each week and about 16 rows one for each hospital ...
amankedia's user avatar
13 votes
1 answer
9k views

What is the difference in xgboost binary:logistic and reg:logistic

What is the difference in R in xgboost between binary:logistic and reg:logistic? Is it only in evaluation metric? If yes, how does RMSE on binary classification compare to error rate? Is the ...
user2530062's user avatar
2 votes
1 answer
41 views

What knoweldge framework supports this type of query?

I have knowledge that is organized as in the example below, where items or nodes can belong to multiple hierarchies and can have arbitrary numbers of children and parents: ...
Andrew73249's user avatar
4 votes
1 answer
1k views

Parallel Q-learning

I'm looking for academic papers or other credible sources focusing on the topic of parralelized reinforcement learning, specifically Q-learning. I'm mostly interested in methods of sharing Q-table ...
Luke's user avatar
  • 189
1 vote
2 answers
1k views

Running examples from scikit-learn tutorials

I am new to scikit-learn. I went through the examples given in the docs and I downloaded the script for recognizing images of hand-written digits. When I made the script to run on my laptop, I got the ...
enterML's user avatar
  • 3,031
1 vote
1 answer
216 views

How to define person's gender from the fullname?

Given person's name, e.g. 'Adjutor Ferguson'. How to define is it a male or female? One solution came to my mind: ...
GML-VS's user avatar
  • 113
28 votes
2 answers
24k views

Predicting a word using Word2vec model

Given a sentence: "When I open the ?? door it starts heating automatically" I would like to get the list of possible words in ?? with a probability. The basic concept used in word2vec model ...
DED's user avatar
  • 345
4 votes
2 answers
1k views

Using machine learning specifically for feature analysis, not predictions

I'm new to machine learning and have spent the last couple months having a blast using Sci-Kit Learn to try to understand the basics of building feature sets and predictive models. Now I'm trying to ...
Matt Harvey's user avatar
2 votes
1 answer
720 views

Combining K-means clustering with Agglomerative clustering

I am trying to identify 6 clusters in a graph of authors. Authors are connected with an edge when they have co-authored on a paper. I have already created a clustering with K-means (6-Means) and with ...
G. Derks's user avatar
3 votes
2 answers
10k views

One-Hot Vector representation vs Label Encoding for Categorical Variables

I have one categorical variable of string type in my dataset. I need to convert it to numerical value for further processing. I know standard way to represent categorical data is to use one-hot ...
SHASHANK GUPTA's user avatar
10 votes
1 answer
3k views

Why is Reconstruction in Autoencoders Using the Same Activation Function as Forward Activation, and not the Inverse?

Suppose you have an input layer with n neurons and the first hidden layer has $m$ neurons, with typically $m < n$. Then you compute the actication $a_j$ of the $j$-th neuron in the hidden layer by ...
Manfred Eppe's user avatar
1 vote
2 answers
114 views

Datamodel for cluster analysis terms & segmentation

Hey fellow data lovers! I have a data modelling problem for a clustering analysis that I can't wrap my head around. Perhaps I'm thinking to advanced and I should simplify my analysis. I have 2 data ...
Tankske's user avatar
  • 11
5 votes
3 answers
4k views

Best regression model to use for sales prediction

I have the following variables along with sales data going back a few years: date # simple date, can be split in year, month etc shipping_time (0-6 weeks) # 0 weeks means in stock, more weeks means ...
noobstats's user avatar
1 vote
1 answer
80 views

Feauture selection for clustering regarding zero-correlated feature

I want to cluster a 5 feature data-set. Firstly to explore the data I did a correlation matrix to see if some features where highly correlated so I could reduce them. Then I saw a feature that have ...
20-roso's user avatar
  • 680
11 votes
4 answers
10k views

Overfitting/Underfitting with Data set size

In the below graph, x-axis => Data set Size y-axis => Cross validation Score Red line is for Training Data Green line is for Testing Data In a tutorial that I'm referring to, the author says ...
tharindu_DG's user avatar
2 votes
0 answers
100 views

Does Apche Kafka support sockets-based communication?

Does Apche Kafka support sockets-based communication? Example: After running both Kafka producer and consumer.if I send a message through putty(TCP/IP client), will the consumer receive it or not?
user1926061's user avatar
7 votes
3 answers
2k views

How do I choose a discount factor in Markov Decision Problems?

I'm referring to the gamma in the Value function:
Austin Capobianco's user avatar
4 votes
2 answers
707 views

Simple Explanation of Apache Flume

Can anybody explain Apache Flume for me in a plain language? I'd appreciate an explanation with a practical example instead of abstract theoretical definitions, then I can understand better. What is ...
DanielWelke's user avatar
3 votes
2 answers
2k views

Simple Explanation of Apache Kafka [closed]

Can anybody explain Apache Kafka for me in a plain language? I'd appreciate an explanation with a practical example instead of abstract theoretical definitions, then I can understand better. What is ...
DanielWelke's user avatar
1 vote
1 answer
1k views

A Simple Explanation of ZooKeeper in Hadoop

Can Anybody Explain me the role of ZooKeeper and ZooKeeper Quorum in a BigData structure? I'd appreciate if you explain me with a simple practical example instead of abstract theoretical definitions. ...
DanielWelke's user avatar

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