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

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Learning the joint probability distribution of 3 variables from partial observations

I have a dataset composed of 3 random variables X, Y and Z. However, at each sample one of the random variable remains hidden. As an arbitrary example, the observation 1 is $(x_1,y_1)$, the ...
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8 views

Comparing corpuses with different vocabulary?

How can we compare two corpuses with different vocabulary? Basically, we have a bunch of distributions for different vocabularies that we want to compare. But all the vocabularies are different ...
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7 views

Almost a multinomial logistic regression

Is there a way to train a multinomial logistic model where the true classification is unknown, but summary information obtained from the true classifications is known? Illustrative Example: 5 ...
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1answer
14 views

Validation of Support Vector Machine using sklearn

I have made a recording of two different sounds and I want to use an SVM in order to be able to distinct between the two. The process I have followed is: Divided each sound in multiple 20ms frames. ...
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4 views

Can you help me to plot the result of support vector machine regression using matlab/libsvm?

Can you help me to find the code that plotting the result of support vector regression using matlab/libsvm using 6 dimension features and 1 predictor variable?
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21 views

What is the minimum sample size required to train a Deep Learning model - CNN?

It is true that the sample size depends on the nature of the problem and the architecture implemented. But, on average, what is the typical sample size utilized for training a deep learning framework? ...
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2answers
54 views

What is energy minimization in machine learning?

I was reading about optimization for an ill-posed problem in computer vision and came across the explanation below about optimization on Wikipedia. What I don't understand is, why do they call this ...
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17 views

What is discretization in machine learning? [on hold]

Why do we need discretization? which classifier is needed for discretization?
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35 views

What it mean by Training SVM

I am new to image processing. As my project I am doing "image classifier using SVM". I have the idea of my final software "I select some image and give it as input to my software and it will classify ...
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27 views

What is the Bernoulli class conditional distribution?

What is the Bernoulli class conditional distribution? I am trying to implement a procedure for computing a naive Bayes classifier for binary features with a Bernoulli class conditional distribution. ...
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22 views

Using Deep-Learning for Cancer Detection [on hold]

I am going to work on a project which main topic is to analyze patients' medical images in order to know whether he is affected by cervical cancer or not. The Machine Learning technique which has to ...
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15 views

Which machine learning approach/algorithm do I choose for path validation?

I apologize for lack of terminology, I'm no computer scientist. I have a problem of validating paths in a directed graph with complex nodes. The full description is the following: I have a decent ...
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9 views

How to implement Vectors in Feature Vector?

Please change the question title if you find a better one for my problem. I have taken some measurements with a 6 DOF (accelerometer and gyro) sensor. Now I want to use this data for a classifier ...
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14 views

SVM file preparation [on hold]

I have a file in which i have comma separated value like this 0.000,17.021,8.511,6.383,4.255,6.383,4.255,2.128,10.638,6.383,0.000,8.511,4.255,0.000,8.511,6.383,4.255,0.000,2.128,0.000 ...
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23 views

has anyone tried to use spectrum kernel [duplicate]

Can any one explain me how to use string kernels to quantify the similarity between short texts? thank you. regards
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0answers
23 views

Meaning of “reconstruction error” in PCA and LDA

I am implementing PCA, LDA, and Naive Bayes, for compression and classification respectively (implementing both an LDA for compression and classification). I have the code written and everything ...
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1answer
22 views

Computing the Interaction gain. Is there an Error in the infotheo package in R?

In order to implementing a certain feature selection method for a classification problem I need to estimate the the interaction the interaction gain between two features and the target variable which ...
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25 views

Is dimensional reduction using Autoencoders possible with a small sample size?

I have a data set that is not too big but high dimensional, let say 10000 dimensional. I want to use an autoencoder to extract relevant features (clusters) in the data. Usually when I have seen ...
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25 views

What does make SVM a “soft computing” method?

Soft computing is defined in [1] by the capability of "operating with uncertain, imprecise and incomplete information in a manner that reflects human thinking". So, based on my limited understanding, ...
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2answers
30 views

Dynamical time warping for dynamical system classification

I am trying to find a way to classify and segment a large set of time series that each individually describe a dynamical system. I wanted to know if the following idea for doing so is a feasible ...
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10 views

model to learn graph

I'm looking for machine learning techniques which allow me to obtain a model learning relationship of graphs. In a basic regression problem, model learns a relationship between real values. A model ...
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0answers
8 views

AdaBoost - How to use the distribution D [on hold]

I am trying to implement AdaBoost algorithm in Python. I have m weak classifiers in list called classifiers. I have vector _D ...
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1answer
20 views

clustering evaluation for a special case

In my dataset each point comes from one of 3 classes, so the true labels are like [0,1,0,0,0,2,1....]. I have to cluster them in 200 clusters. I want each cluster ...
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9 views

Sequence analysis with multiple sequences

I would like to recognize different states in a sequence of multiple vectors. To make it little more clear, here is an example: I have 2 (or more) vectors in a sequence: head position(HP) and eye ...
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14 views

Calculate state change probability

I am having telco order management data and need to calculate the probability of each order going through different stages. data is like this: Order No; product_type; time spent in step1; time ...
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3answers
67 views

Why do we do hypothesis testing on estimates of linear regression?

I was reading about linear regression and what I understood is that once we minimize OLS equation we get the beta parameters. Its just like solving a normal equation to get the unknowns. Then why do ...
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19 views

Relation between precision, recall and sample size

I have a large data set for binary classification problem. Now in order to fit model to data I have been trying modeling using various sample size. For each sample size I gets a different precision ...
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3answers
1k views

In machine learning, why are superscripts used instead of subscripts?

I'm taking Andrew Ng's course on Machine Learning through Coursera. For equations, superscripts are used instead of subscripts. For example, in the following equation $x^{(i)}$ is used instead of ...
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15 views

SMOTE algorithm how to select over and under percentage?

I have a highly unbalanced binary dependent variable (i.e. cases of '1' is <5%). I am trying to implement SMOTE algorithm using R DMwR package. I wonder in general, how we determine the parameters ...
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39 views

Confused Scikit results

I am doing classification machine learning on a particular dataset on which an SVM model (using Scikit.learn) is giving a Matthew's correlation coefficient (MCC) of ...
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16 views

Suggestions for Neural Network Structure for Time-Series prediction with constant covariates

I've been working on a time series prediction problem and wondered if someone has run across a similar problem structure & can make a suggestion on how to structure the training data, network, or ...
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41 views

Which machine learning technique is appropriate for my problem?

I'm new in machine learning topics and I've problem in modeling my environment which has multi parameters with different value ranges and a few actions to perform when value of each parameter is not ...
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30 views

How to correctly build a training/validation/test?

I have a database that is comprised of 3 sets of data. The first created in office conditions, the second in the same office taken on different day and the third drawn from random images from the ...
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8 views

Feature scaling when using Rectified Linear Units [duplicate]

Is it necessary to scale the input data of a Neural Network to a certain range (e.g. 0 to a big number) if the activation function consists of ReLus?
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22 views

Normalization after PCA Whitening (for Deep Learning)

When training a Deep Learning model like an auto-encoder, is it necessary to normalize data again after it has been processed by PCA Whitening? Right now I zero-mean my data before PCA and use the ...
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21 views

Converting between different accuracy/error metrics

I am trying to compare model accuracy between several different measurement metrics. For example, some citations use accuracy while other use error. That one is rather obvious, but there are lots of ...
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31 views

How do I get initial transition matrix probabilities?

I have to develop a system to detect and prevent bank transactions fraud - just credit card transactions, for simplicity - I'm thinking about using markov chain. How would I get the initial ...
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25 views

Terminology clarification: Discrete distribution == Categorical distribution?

I'm reading "The Indian Buffet Process: An Introduction and Review" by Griffiths and Ghahramani and wanted to confirm my understanding of one of the terms they use. On page 1188, they say that the ...
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19 views

How do I reduce number of features without rebuilding the model?

I'm pretty new to ML/NLP thus my question maybe naive. How do I reduce number of features without rebuilding the model for Naive Bayes Classification? I'm using MALLET to build the model to classify ...
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0answers
10 views

Mixture of experts learning with unlabeled data and a fitness function

I have a classification problem. It essentially amounts to sorting a large number of integer vectors into a small number of categories. The samples are completely unlabeled, and even I do not know how ...
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1answer
25 views

Levels of “hyperparameterization” in Hierarchical Modeling

Suppose we have observations $y$ that we wish to model as having being randomly sampled from a distribution with parameter $\theta$. General Bayesian approach assumes a prior distribution over ...
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6 views

Implementing a model for 'Flash Fill'

MS Excel (since 2013) offers a Flash Fill feature that learns how you want to transform columns in your spread sheet based on training data for some rows and then applies this transformation on all ...
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21 views

Chinese restaurant/Dirichlet process get the hyperparameters from already clustered data

Imagine I have already some N clusters (or filled tables in CRP terminology), is there a way to estimate the hyperparameters alpha, theta (wiki terminology ...
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2answers
35 views

How to calculate distance between points in DBSCAN matrix data? [on hold]

I'm making a simple C implementation of DBSCAN following his pseudocode. If I well underand how DBSCAN works, I may represent my set of N elements (each with M features) with a NxM matrix. When it ...
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0answers
21 views

Impact of data distribution on (statistical/ machine) learning performance: overview

I am trying to get a global view on the different ways how (non-ideal, messy) data distributions can affect different performance dimensions of statistical/machine learners, incl. but not limited to: ...
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1answer
35 views

Overfitting and Data splitting [closed]

Let's say that I have a data file like: Index,product_buying_date,col1,col2 0,2013-01-16,34,Jack 1,2013-01-12,43,Molly 2,2013-01-21,21,Adam 3,2014-01-09,54,Peirce 4,2014-01-17,38,Goldberg ...
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1answer
91 views

Machine learning on dummy variables

I have a dataset on which there are about 1000 dummy variables indicating location. I do not have access to lat/long. I am using xgboost to train it. The more that I train it does seem to be lowering ...
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42 views

How to boost the performance of support vector machine?

I have 4 different data samples: Stage 1: [152 X 27578] Stage 2: [48 X 27578] Stage 3: [48 X 27578] Cancer: [63 X 27578] Each sample are the different stage of cancer in descending order. Here I ...
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24 views

Reasonable R² for a Machine Learning Problem [closed]

I got a R² of 3.6 in a competition of Machine Learning which were not disclosed meanings of variables. I am using XGBoost method. Is this number unacceptable for this type of problem or may have ...
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17 views

Select and weigh questions on a reading assessment

I am a phd student in computer science and as such I am the goto guy for anything "mathy" in the cross discipline research group to which I belong. I have recently been given an assignment at work I'm ...