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

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Duda, Hart, Stork No Free Lunch Discussion

Please see this question regarding Duda, Hart, and Stork's No Free Lunch Thm Discussion Hi all, I was having trouble understanding the description of the NFL theorem in Duda, Hart, and Stork. My ...
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1answer
42 views

Predicting the impact point of a moving object

Suppose we have a moving object (a horizontal projectile motion as one of the most basic examples). Is there any way to predict where it will hit finally? Please note that I'm looking for a machine ...
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21 views

How much time is reasonable for training Restricted Boltzmann Machine?

I have implemented Binary RBM in Matlab. I am using 60000 images as an input to train RBM. It takes approximately 11.3 minutes. I used tic and toc functions to evaluate above mentioned elapsed time. ...
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1answer
79 views

Variance-covariance matrix for ridge regression with stochastic $\lambda$

In ridge regression with design matrix $X$, outcomes $y$, fixed regularization parameter $\lambda$, and errors $\epsilon\sim\mathcal{N}(0, \sigma^2I)$, the computations for the ridge regression ...
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16 views

GB-RBM unable to learn and generate simple 2D-Motions?

I am trying to apply a GB-RBM to a variation of the LASA Handwriting Dataset to be able to generate new examples. My dataset contains motion trajectories of simple shapes like 'S' shapes, spirals, 'C' ...
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22 views

Bayesian Perceptron - how can I generate many different perceptrons?

I am going to implement the Bayesian version of a perceptron that I read in the Statistical Mechanics of learning, by Engel-Van Den Broeck. The idea to improve the performance is to use many Gibbs ...
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35 views

Conditional or Joint Probability under Various distributions

In various statistical models the baseline equation (like in Naive Bayes $$\mathrm{classify}(f_1,\dots,f_n) = \underset{c}{\operatorname{argmax}} \ p(C=c) \displaystyle\prod_{i=1}^n p(F_i=f_i\vert ...
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47 views

Where can I use kernels other than Gaussian (like Cauchy, laplacian) in kernel methods in machine learning? Or maybe in kernel density estimation?

In few papers I read that - kernel used doesn't really matter for kernel density estimation but bandwidth of the kernel is the most important factor. But I did not see any mathematical explanation to ...
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5 views

How accurate sum of kernel function needs to be, so that we can use it in Mean shift algorithm (may be for image segmentation)?

Mean shift is a procedure for locating the maxima of a density function given discrete data sampled from that function. It is useful for detecting the modes of this density. This is an iterative ...
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163 views

Ensembles of Ensembles?

I like the idea of ensemble learners, especially Bagging, but I always wondered as why they are not the most powerful learners since they have a clean motivation. I don't have the answer to that ...
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18 views

How to interpret merits in Weka with ChiSquaredAttributeEval and SVMAttributeEval?

I want to interpret the goodness of attributes using feature selection with 10-fold cross validation. With ChiSquared I get something like this (deletet attributes with merrit was 0 in all folds): ...
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24 views

Predict feature combination with highest probability

I trained a Support Vector Machine with the caret package in R. My dataset looks the following: ...
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19 views

Regression line fit for linearly increasing data with manual reset

I've a linearly increasing time series dataset of a sensor with value ranges between 50 to 150 on which I've implemented a simple linear regression algorithm to fit a regression line, and I'm ...
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16 views

Improving sentence segmentation in NLTK

I have been looking into problem of sentence segmentation lately. I have been referring to NLTK's book for this purpose. I followed their procedure to segment sentences presented here: ...
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30 views

What is the simplest way to classify airplan manuvers?

Suppose we have declared four motion types for air-plane. If we represent each maneuver with a trajectory line, what is the best classification method to retrieve the trajectory pattern with a similar ...
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2answers
237 views

Estimate ARMA coefficients through ACF and PACF inspection

I know that this is probably a question that's been asked plenty of times, but i haven't seen an answer that's both accurate and simple. How do you estimate the appropriate forecast model for a time ...
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12 views

determing states in HMM with BIC

I'm fitting a HMM to time series, for each data set I use BIC results to select the optimum number of states. In that, the BIC number is lowest and thereby indicating this model with that number of ...
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1answer
104 views

Is KNN a discriminative learning algorithm?

It seems that KNN is a discriminative learning algorithm but I can't seem to find any online sources confirming this. Is KNN a discriminative learning algorithm?
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10 views

Turning MiniBatchKMeans into Fuzzy MiniBatchKMeans

I'm using Scikit-Learn, which has an implementation of MiniBatchKMeans. I'm very inexperienced with ML, so I'm wondering how (if ...
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3answers
117 views

Best way to turn a date into a numerical feature?

I have a fairly large dataset with a few fields containing time-related data. This data comes in various shapes and sizes, but most of it can be parsed and rephrased in more appropriate formats for ...
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1answer
44 views

SVM cost parameter

In a SVM with linear kernel, could you explain to me what exactly the C parameter is/represents? An example why it's important to select a good value for C would also be appreciated. Thank you.
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1answer
83 views

Maximum Entropy Model for classification, what to use as context & feature?

I'm building a Maximum Entropy Model to classify some text, based on paper "A Maximum Entropy Approach to Natural Language Processing" by Berger et.al. It's similar to POS tagging. Below is some ...
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43 views

What is this problem called in machine learning research?

Given 2 sets of entities from 2 different classes described by properties $f_1...f_n$, any 2 entities from the 2 different classes together have a score: ${\rm Score}(c_1e_1,c_2e_1) = y$. How ...
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1answer
88 views

The usage of data mining in pharmaceutical companies?

I know that data mining applications are being used in pharmaceutical companies, but my question is: what do they use them for? Sometimes I read: "drug discovery", but how? How is it used for drug ...
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10 views

how to create labeled term to document matrix for classification for TMG

I already asked the same question but not got any reply. Please any one help me. I have created term-to-document matrix for document collection. I want to classify them with TMG (Term to matrix ...
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21 views

What are some multivariate models with feature interactions

I have dependent variable matrix $Y_{i,j}$ and feature matrix $X_{i,k}$. My objective is to predict each element of the vector $[y_{i,0},...,y_{i,J}]$ by using new observations of the features, ...
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52 views

Training and testing on Unbalanced Data Set

I used SMOTE algorithm in R for class balancing. My data size has 13000 rows, I had 7% minority class in my sample now I used SMOTE( Synthetic Minority Oversampling Technique) for class balancing such ...
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1answer
28 views

how to handle (many) false positives in training dataset for logistic regression classifier

I want to train a logistic regression dataset. I have a quite big training data set ( >100 000) and have around 10 features I can train on. Half of my training data is negative training data and I ...
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10 views

Latent semantic classification

How can I create a training data set for document classification using LSA? I have created a term-to-document matrix and have class labels also. I don't know whether to add these class labels in a ...
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31 views

How to choose the proper supervised machine learning algorithm

I have following data: ultra-sound audio recording, and I have the raw data of those samples, and of course the Fourier Transform data for those samples. Each dataset is assigned a value (for example ...
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1answer
73 views

Example of how the log-sum-exp trick works in Naive Bayes

I have read about the log-sum-exp trick in many places (e.g. here, and here) but have never seen an example of how it is applied specifically to the Naive Bayes classifier (e.g. with discrete features ...
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1answer
44 views

What is the difference between a “learner” and “classifier” in supervised learning?

This question stems from Pedro Domingos' excellent paper "A Few Useful Things to Know About Machine Learning." The paper is extremely clear and well-written, but I still have a clarification question. ...
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1answer
170 views

Stochastic Programming with MCMC

I have just started learning about MCMC (using PyMC), and it seems to be a hammer that can be used to solve a large class of inference and optimization problems. While I understand that there are ...
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56 views

Way to train Hidden Markov Model in R with multiple sequences

i have multiple sequences for each of two states. I'd like to train a HMM with these to predict the state for unkown sequences. Here is an example for this problem: ...
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10 views

Prediction with not atomic features

I would like to use another type of data, not atomic data, as a feature for a prediction. Suppose I have a Table with those Features: - Column 1: Categorical - House - Column 2: Numerical - 23.22 - ...
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1answer
53 views

How to prepare interactions of categorical variables in scikit-learn?

What is the best way to prepare interactions of categorical features before fitting with scikit-learn? With statsmodels I could conveniently say in R-style ...
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51 views

What algorithms should I use to perform job classification based on resume data?

Note that I am doing everything in R. The problem goes as follow: Basically, I have a list of resumes (CVs). Some candidates will have work experience before and some don't. The goal here is to: ...
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45 views

Predicting the Success of a tweet

I want to predict the success of a tweet. In my case a tweet is successful when the sum of the number of favorites and the number of retweets is greater than 5. So my outcome value y is: y= ...
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1answer
90 views

Feature selection : how to select the Information Gain threshold?

I am trying to use Information Gain to select features when classifying text with a Support Vector Machine. For each word in our training data, we computed its information gain. Then, we should keep ...
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1answer
50 views

The efficiency of Decision Tree

When we use top down approach to induce a decision tree, we need to use some kind of splitting criteria to choose the splitting feature and splitting value at a certain internal node. The criteria ...
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34 views

Multiple Discriminant Analysis, Linear Discriminant Analysis, and Multidimensional scaling - how are they related?

Some time ago when I took a Pattern Classification class, the "concept" was introduced as Multiple Discriminant Analysis: You want to project your data onto a subspace (if you are interested in ...
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29 views

K-means Stuck in 1 cluster

I'm working on a problem using the encog Kmeans library and NO MATTER what features I add to the model, it always gets stuck in one of the clusters. ALL of the samples are lumped into one cluster ...
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19 views

How to correctly concatenate time series data

I have this shifted time series data. For one set consists of features from week1-5 and labels at week6. Another set features from week2-6 and labels and week7 and so on. I have like four sets of ...
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65 views

Decision tree in R

I am new to machine learning in R. This is my data set. ...
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14 views

Posterior Marginal in Forward Backward

In computing Forward Backward Algorithm[http://en.wikipedia.org/wiki/Forward%E2%80%93backward_algorithm], it seems they are calculating posterior. I knew Forward Backward is an algorithm of ...
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1answer
59 views

Predictive analysis of data using R

I am trying to analyze data to predict the effect of 8 predictors on a response variable. I ant to do it using R. There are 8 predictor variables (x1, x2, ..., x8) and one response variable (y). I ...
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1answer
38 views

Data preparation and machine algo for ad click prediction

I am an ml noob. I have a task at hand of predicting click probability given user information like city, state, os version, os family, device, browser family browser version, city, etc. I have been ...
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50 views

How to prepare data for classifiaction

I have a relative small dataset that is consisted of numerical, nominal as well as text features. Some cells are empty whereas the class type is nominal and can take any of the ~10 different ...
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13 views

Can LSA find correlations between multiple words?

I need to find correlations between multiple terms (say, 3 or 4) in a single-term search index. I'm trying to figure out if LSA fits to the problem. Am I right that LSA is no more than a term-to-term ...
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20 views

How to increase a particular terms's weightage?

I am doing Text classification using LibSVM in Rapid Miner. I am using TFIDF values for processing documents. I need to Increase weightage of some terms in the documents(for eg. words in BOLD and ...