Methods and principles of building "computer systems that automatically improve with experience."

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Why is the energy and the probability of a configuration related in a Boltzmann machine?

According to Hinton's slides (slide 34) the following relationship holds for Boltzmann Machines in thermal equilibrium: $$ p(v,h) = \frac{e^{-E(v,h)}}{\sum_{u,g}{e^{-E(u,g)}}} $$ To me this is not ...
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25 views

How is bootstrapping used for machine learning?

How does one use bootstrapping in a machine learning context? My typical data analysis pipeline is Split data into 10 folds Train classifier with 9 folds Test classifier with remaining fold Repeat ...
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19 views

Get important features of n samples

Suppose I have a data frame of [n_samples, m_features] with the corresponding variances of the features [n_features]. The values in my data is between 0 and 1 so the question is: Is there any way to ...
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19 views

How can I make Weka classify the smaller class, with a 2:1 class imbalance?

How can I make Weka classify the smaller classification? I have a data set where the positive classification is 35% of the data set and the negative classification is 65% of the data set. I want Weka ...
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15 views

Time-series cross-sectional classification problem

I have a time-series cross-sectional dataset consisting of 100 individuals that each had 4 features measured yearly for 21 consecutive years. One of the features is binary and the other three are ...
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5 views

How can I use Extreme Learning Machine in Rapidminer? [on hold]

I am working on a problem, I need to use 'Extreme Learning Machine.' But I don't know any programming language. I use Rapidminer. Is it possible to use the algorithm on Rapidminer?
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17 views

Representation of misspelled words for neural network?

While thinking about a neural network based spellchecker, I was thinking about word embedding not being able to represent any "unique" (misspelled) words that the model haven't seen before. I tried ...
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21 views

Adaboost step by step

So I have a table with 2 classes and binary data. D1 is the expected output and I have to perform Adaboost , to combine the classifiers in order to get the best result.(for example in row 1, BN(N3) ...
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9 views

how can fixed parameters cost and gamma using libsvm matlab to improve accuracy? [migrated]

I use libsvm to classify a data base that contain 1000 labels. I am new in libsvm and I found a problem to choose the parameters c and g to improve performance. First, here is the program that I use ...
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5 views

Regarding pattern recognition and forecasting next set of sequence [on hold]

I have been working on use case where I have some sample data as below : Date Device Name Time Facility Code 1/6/2015 Tablet X 16:18:48:168 22 A 1/6/2015 Tablet X 16:18:50:41 ...
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22 views

Kernel K nearest neighbours with sparse data

I have a big sparse matrix (around 5 million of lines, 20 000 predictors), and I would like to run a kernelized k-NN on it. However, I don't know how to scale the data properly. So far, I have scaled ...
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59 views

Improving a logistic regression model in R [on hold]

I have to devise a model in R, capable of predicting the type of a disease, which is a categorical dependent variable (three possible values), through several continuous and categorical, some of the ...
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7 views

mahout kmeans class not found exception [on hold]

I have configured Hadoop in Psuedo-Distributed mode. I have succesfully created sequence-files and tf-idf vectors(using seq2sparse) and am trying to run mahout kmeans from command-line as follows: ...
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14 views

What techniques infer dependencies between time series?

I'm working on an ML project. We have an app where users can track 1) binary variables and 2) quantities over time on a scale from one to ten. For example, at a given time they may track whether they ...
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12 views

VC Dimension of the set of canonical hyperplanes

This is a proof of the theorem about VC Dimension of the set of canonical hyperplanes from Professor Mohri's lecture slide. I'm having difficulty with understanding the inequality$$ \forall i \in ...
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21 views

Upcoming areas in theoretical Bayesian Machine Learning [on hold]

I will soon be going for a postdoc position at a new university. One thing that the panelist asked me to think of is if I were to start, what would I work on. Now the thing is so far with my PhD ...
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21 views

Advanced Method in Machine Learning to Learn Objects Position

I have done research about tracking of human body, face, hands, pedestrian etc. Can you point me to the methods in machine learning that learn the changes in position of multiple objects for object ...
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5 views

RSNNS neural networks, checking percentage correct.

For those who have some experience with RSNNS, I'm trying to build a neural network for reading aloud, using RSNNS in R. To give some information about what I'm doing and using. I'm using orthographic ...
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18 views

Is there a difference between on-line learning, incremental learning and sequential learning?

What I mean is the following: Instead of processing all the training data at once and calculating a model or hypothesis, we process one data point at a time and update the model directly afterwards. ...
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7 views

How should I measure difference between user behavior / model performance on different population?

I am developing a recommendation engine whose goal is to suggest data exploration routes to non-technical users. The underlying model is content based, with the training data made up of the behavior ...
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13 views

How to use Particle Swarm Optimization for finding optimal bandwidth with cross-validation?

I want to use Particle Swarm Optimization (PSO)for finding optimal smoothing parameters of a kernel density estimation problem. Initially I tried to find the same using grid search method,but the ...
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7 views

Touch times to authenticate user

for a project I gathered touch data of different users when they tap a rhythm repeatedly on the touch screen in a game. ...
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58 views

how to solve an optimization problem? [on hold]

I am reading an article with title "Learning a distance metric from relative comparisions" lately. http://www.cs.cornell.edu/people/tj/publications/schultz_joachims_03a.pdf. The basic idea for this ...
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8 views

Scikit Random forest pred_proba gives rounded off values

I am using random forest in scikit learn for classification and for getting the class probabilities , I used pred_proba function. But strangely it outputs probabilities rounded to first decimal place ...
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2answers
32 views

Name some techniques similar to Random Forests

I'm interested in what techniques are out there that are similar to, but not the same as, Random Forests. Either for classification or regression or both. Particularly interested in techniques which ...
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31 views

SKLearn Clustering: how would you cluster a LARGE database of dogs? [on hold]

Given: A VERY large dataset of dogs. columns: ID (alphanumeric) Weight (numeric) Height (numeric) Eye Color (alphabet) ... (numeric) Tongue Length (numeric) How do you find what makes these ...
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40 views

Fitting a trading model [on hold]

I have a high frequency time series of the bid and ask prices of a stock recorded on every tick. For each data point I also have a certain indicators that predict the future movement of the price. The ...
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1answer
36 views

Weight shrinking in linear regression by L2 regularization

Quoting Prof. Bengio from his Deep Learning text (http://www.iro.umontreal.ca/~bengioy/dlbook/regularization.html), $ w = (X^{T}X + \alpha I)^{-1}X^{T}y $ We can see L2 regularization causes ...
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7 views

Reduce the FP rate for a Random Forest (sklearn)

I am working with the scikit-learn random forest classifier and I want to reduce the FP rate by increasing the number of trees needed for a successful vote from greater than 50% to say 75%, after ...
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10 views

How to model the problem of predicting failure in Server Clusters

The problem goes as follows - There is a cluster of Servers. Whenever there is failure/anomaly in any of the server, a report is logged. Some of the features of the log report are Time of Failure ...
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10 views

Website classification using metadata features

I want to fit a model that predicts a website type according to metadata features that I manually collected, such as - Average text length, average # of pics, average outgoing links per page, etc... ...
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20 views

Getting an error message “Error in if(reached.threshold < min.reached.threshold)…” while training network using neuralnet package

I'm using R to create train and test a neural network on a time series (the annual sales of a company over a large period of time). As using the package's default learning algorithm (resilient ...
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3answers
495 views

What can we learn about the human brain from artificial neural networks?

I know my question/title is not very specific, so I will try to clearify it: Artificial neural networks have relatively strict designs. Of course, generally, they are influenced by biology and try to ...
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73 views

Why is SVM better for bioinformatics analysis?

I have used five different algorithms: bagging, boosting, C4.5, random forests and SVM, for binary classification of biological data relating to peptide sequence. The dataset comprised of ...
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2answers
39 views

what is the difference between area under roc and weighted area under roc?

Thanks in advance for the help. I have an unbalanced dataset that I am using for a binary classification problem. The classes are unbalanced. I believe that in such a case that weighted area under ...
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13 views

how to understand this neighborhood components analysis model?

I am reading an article with title "neighborhood components analysis" lately. http://papers.nips.cc/paper/2566-neighbourhood-components-analysis.pdf. This article is trying to introduce a linear ...
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1answer
43 views

How to use linear regression for heavily skewed purchase data?

I am trying to use multiple linear regression to predict the amount that a particular user will spend in a particular time frame on a particular site. Part of the problem is that there are very few ...
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1answer
48 views

In a Boltzmann machine, why isn't there a simple expression for the optimal edge weights in terms of correlations between variables?

Suppose I have a fully connected, fully visible Boltzmann machine (no hidden variables) with binary variables $x_i\in \{+1, -1\}$ that defines the probability distribution $$ p(\mathbf{x} ; ...
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13 views

when to stop this convex optimizations algorithm?

I am reading the article with title "metric learning with collaping classes" lately http://papers.nips.cc/paper/2947-metric-learning-by-collapsing-classes.pdf. See this thread (what is 1/0 in this ...
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18 views

Active acquiring as a special case of active learning

I explore an approach for collecting data. This approach is similar to active learning, but there are few differences. The focus of the approach is on collecting training data (labeled data) ...
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1answer
44 views

train an SVM via back propagation?

I was wondering if it was possible to train an SVM (say a linear one, to make things easy) using back propagation? Currently, I'm at a road block, because I can only think about writing the ...
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3answers
57 views

Use Edge detection in Image classification

I am having five types of objects (flower, building, face, pair of shoes and a car) in my object recognition and i need to classify these. Identifying through edges in this type of data set seems to ...
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4answers
964 views

Why is Logistic Regression called a Machine Learning algorithm?

If I understood correctly, in a Machine Learning algorithm, the model has to learn from its experience, i.e when the model gives the wrong prediction for the new cases, it must adapt to the new ...
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1answer
43 views

What does “node size” refer to in the Random Forest?

I do not understand exactly what is meant by node size. I know what a decision node is, but not what node size is.
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1answer
47 views

Anomaly detection in time series data

Hi I have a large data set of objects, each containing a list of the same attributes. The data is arranged in a time series so that the value for an attribute for an object is indexed by its time. I ...
3
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1answer
15 views

nested cross-validation

if my outer cv is 5-fold, after the process, i have 5 final models, then apply these 5 final models from each CV to the whole dataset (training+validation+testing). For my case, the final 5 accuracy ...
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1answer
28 views

Using Fisher LDA in R

I have run a large study looking at traumatic brain injury in patients I have conducted CT scans on patients very soon after the injury as well as neurocognitive testing and then repeated this at 1 ...
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33 views

Can I Interpret the impact of variables like positive or negative on the model by Random Forest, as I can do by Logistic Regression

I have created a model for prediction of candidates presence or not . I have used Logistic Regression and Random Forest . By Logistic Regression, I got coefficients associated with 100 features and I ...
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1answer
28 views

Independence of data points assumption

While reading an ML book, I realized that most of the time, the input data points are correlated with each other, and hence their observation is not independent. But then, why do we assume that the ...
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R | NA/NaN/Inf in foreign function call | e1071 SVM [migrated]

Dataset: https://archive.ics.uci.edu/ml/datasets/Chess+%28King-Rook+vs.+King-Pawn%29 Code: ...