0
votes
0answers
11 views

How to prepare my data for SVM classifier in matlab

I am new to SVM and Matlab. I would like to have an example how to prepare my data to be as input to the SVM classifer (using libsvm) let us assume that i have a group of words first i have ...
0
votes
1answer
29 views

Whats going wrong in Implementation of this gaussian bernoulli RBM?

I have a problem in finding negdata value. In particular multiplying with sigma. Could someone help in representing this equation vishid*sigma*poshidstates + visbias in matlab. ...
0
votes
0answers
21 views

Custom Neural network in matlab

I am trying to make a custom Neural network structure using 'network' command. I am a little confused.Can we change the connections between individual neurons?Like it is possible in weka?
0
votes
0answers
43 views

MATLAB interperetation of Neural networks

I am new to Neural networks and I am trying to build a custom neural network using the NN toolbox in MATLAB.I am using the "create custom neural network function". Now, I find the neural network ...
0
votes
0answers
127 views

10 fold cross validation model in weka

Trying to build a specific Neural Network arcitecture and testing it using 10 fold cross validation of a dataset. Now building the model is a tedious job and Weka expects me to make it 10 times for ...
0
votes
0answers
56 views

How to implement data I have to svmtrain() function in MATLAB?

I have to write a script using MATLAB which will classify my data. My data consists of 1051 web pages (rows) and 11000+ words (columns). The first 230 rows are about computer science course (to be ...
0
votes
1answer
49 views

A way to use GPU hardware in matlab [closed]

I know that theano is a python library for using gpu hardware and make effective implementations. Is there any such library or a way to do the same in matlab?
0
votes
1answer
185 views

Explanation of the Regression Plot in the Matlab Neural Network Toolbox

What does the Regression Plot in the Matlab Neural Network Toolbox show? I thought I understood it when I looked at a univariate regression plot, but I've just plotted one for multivariate regression, ...
0
votes
0answers
96 views

Set up a classification experiment via libsvm (MATLAB)

I would like to set up an experiment in MATLAB, to predict the class of a set of text instances in a two-class problem (e.g., the text talks/does not talk about ...
1
vote
0answers
71 views

How can I improve the accuracy of my logistic regression code, which tests the accuracy using the 10-fold cross-validation technique?

How can I improve the accuracy of my logistic regression code, which tests the accuracy using the 10-fold cross-validation technique? I have implemented this code using ...
0
votes
0answers
51 views

Cross validation MATLAB code for multi-output regression

I am using multi-output support vector regression (MSVR) which predicts multiple outputs at a time. I want to know how can I initially select parameters for my model, and then how to do cross ...
0
votes
0answers
37 views

Performance comparsion study on real data in MATLAB (machine learning)

I need to compare performance using 2-class classifiers–an LDA classifier and Exact Bayes in MATLAB. I have to use this dataset. Can anyone give me any advice how to do that (at least the steps of the ...
-1
votes
1answer
110 views

Is it OK to increase validation checks and decrease min gradient while training neural network?

My input vector is a 130*85 matrix and my target vector is 130*26 matrix. I am using the below parameters for training the network with 60 hidden nodes. ...
0
votes
1answer
85 views

Classification accuracy

I am classifying text based on news headlines and I am achieving accuracy up to approx 80%. I want to improve it more. But issue is that when I calculate the same with synonyms using the code below: ...
0
votes
1answer
65 views

Performing hierarchical clustering on a large data set

I have been applying complete linkage on about 5,000 points using matlab with no problem. I want to extend this method to much more elements. It would take me a long time to process my data to test ...
1
vote
1answer
64 views

Linearly dependent features

I have a matrix A of 1000 observations (rows) and 100 features (cols). I would like to find: Linearly dependent features so that I can remove them and simplify the problem. rank(A) gives me 88, ...
1
vote
3answers
653 views

How to calculate disparity of two images in matlab?

I have two images and I am trying to calculate the disparity between them using sum of squared distances and reconstruct disparity in 3D space. Do I need to rectify the image before calculating ...
0
votes
1answer
105 views

Issue in training Hopfield network and convergence problem

I am learning how to use Hopfield Neural network as a context addressable memory. The objective is to obtain a fixed point of the network which indicates an equilibrium state. This state vector ...
0
votes
0answers
20 views

Low accuracy for training in image classification

I'm a newbie using LinearSVM to train the classifier. I labelled the images of 'buildings' as 1 and the others as -1. The training result is as follows : and As you can see in the image some of ...
0
votes
1answer
150 views

Supervised learning : Hebb learning rule doubts

(A) In this book "Introduction to Neural Network using Matlab 6.0 - S. N. Sivanandam, S. N Deepa" ...
4
votes
2answers
449 views

What tools do Machine Learning experts use in the real world?

I'm currently taking a class covering some topics in machine learning. The class is taught in MATLAB using Liblinear so far. I was curious though what kind of tools people used in the real world to ...
0
votes
1answer
201 views

Using LibSVM for anomaly detection

Im trying to create a one class SVM using libSVM. However whenever I run the svmpredict function it always return an accuracy of 0%. ...
1
vote
1answer
144 views

SVM training method (or alg.)

I'm using SVM classification (Matlab) within my research works, and I want to know: The advantages and disadvantages of each training algorithm, i.e., SMO, LS and QP In general case, what is the ...
0
votes
2answers
174 views

Test data generation for neural network handwriting recognition

Can someone share some Octave/Matlab code or algorithm to pre-process a photo taken from mobile camera of a handwritten digit. After pre-processing, the data should have similar characteristics to ...
0
votes
0answers
79 views

Hopfield neural net cannot store more than 2 association patterns

I'm just trying to implement a simple discrete Hopfield net using Matlab but there is a problem with my result. As I present two patterns to be stored in my net everything works great and I can ...
0
votes
0answers
77 views

Making feature vector from Gabor filters for classification

My aim is to classify types of cars (Sedans,SUV,Hatchbacks) and earlier I was using corner features for classification but it didn't work out very well so now I am trying Gabor features. code from ...
0
votes
0answers
133 views

SVM: plot multi dimensional data when implementing multiclass one-vs-all or one -vs one?

I have split the multi class svm to several binary classifications and obtained the individual predictions. My predicted labels are saved in a matrix 'predicted_vals' with each row containing ...
2
votes
1answer
582 views

Ensemble classification in MATLAB

I want to use ensemble classifiers for classification of 300 samples (15 positive samples and 285 negative samples, it means binary classification). I extracted 18 features from these samples, all of ...
0
votes
1answer
53 views

Performance difference in clustering algorithm

I have a similar problem area as mentioned Trajectory Clustering: Which Clustering Method? . As per suggestion to use dynamic time warping for aligning the time series, are there any differences in ...
1
vote
1answer
3k views

Using random forest in MATLAB

I am having issues in using random forests in MATLAB. I have features of size 2000 and around 4000 data points. I am trying to learn how to compute random forests in MATLAB using the library Random ...
1
vote
0answers
225 views

Feedforwardnet for XOR

I'm using Matlab Neural Network Toolbox. I want learn feed forward net for my classification problem. But network doesn't learn anything useful, so I start checking network setting. I choose xor ...
0
votes
0answers
477 views

improving fitting results of neural network

I've trained fitnet network for prediction steel's yield stress with MATLAB ann toolbox. The neural network should predict yield stress. I have about 250 vector ...
1
vote
1answer
261 views

Concerns related to neural network matlab toolbox

I have some concerns related to the use of nntool in MATLAB toolbox. Following links like this, I have found that nntool by ...
1
vote
1answer
224 views

K-means clustering for usage profiling

I am trying to use k-means clustering to profile mobile device usage behaviour for IT users. My data consists of different system and user level variable/readings like number of calls/sms, cpu/memory ...
2
votes
1answer
154 views

Issues with implementing neural network

I am trying to use neural network to learn a non linear function mapping input to outputs. However, I am having some issues with it. I used tansig activation function for the hidden layers and for the ...
2
votes
2answers
272 views

Using neural networks for multi target prediction

I have a spatial dataset with some xs and ys at different spatial locations. I want to learn a non linear regression function using neural networks. I looked in to the training data and the outputs ...
4
votes
1answer
570 views

Gaussian Processes: How to use GPML for multi-dimensional output

Is there a way to perform Gaussian Process Regression on multidimensional output (possibly correlated) using GPML? In the demo script I could only find a 1D example. A similar question on CV that ...
1
vote
0answers
90 views

In GPML, why does scaler in Squared Exponent covariance function gets very small?

I'm running regression using GPML with a covariance function being a sum of a Gaussian noise and a Squared Exponent (SE). Input is in R4 and both the input and the output are normalized. I run ...
0
votes
1answer
96 views

GPML returns a negative predictive probability. Why? [duplicate]

I'm using GPML (Gaussian Processes for Machine Learning) v3.2 in Matlab. ...
0
votes
0answers
63 views

Can ITML overfit?

When training using Information Theoretic Metric Learning (ITML), should I be concerned that the algorithm will overfit the data? If yes, what is the best way to avoid it? ...
2
votes
0answers
222 views

How to train SVM correctly on a 1D dataset

I am trying to use svmtrain (Statistic Toolbox) to train a linear (2 class) SVM on a 1D feature vectors. The features are not fully separable and the classes intersect. The naive approach would be ...
1
vote
1answer
3k views

PCA using princomp in MATLAB

I'm trying to do dimensionality reduction using matlab princomp, but i'm not sure i'm do it right. here is the my code just for test, but I'm not sure that I'm doing projection right: ...
0
votes
1answer
180 views

Finding the projection used in multidimensional scaling

Background I have a set of data points in high-dimensional (512D) space that I wish to map to 2D for visualisation. I am interested in observing in 2D the (approximate) relative distances between the ...
0
votes
1answer
368 views

Most effective SVM implementation for large classes and datasets?

What's the best SVM implementation of SVMs in MATLAB? Right now I'm looking at PEGASOS and SVM-Perf, which both claims to have good performance with large datasets and classes. But there are so many ...
2
votes
2answers
2k views

How to analyse the effect of changing parameters in a neural network?

I have built a simple classification neural network with feed-forward and backpropagation and one hidden layer (code below) and I would like to explore the effect of changing: - the learning rate - ...
0
votes
1answer
598 views

Using GPML in Matlab for MultiClass Classification

I am using Rasmussen's GPML code in Matlab R2011a_student. I have training data (2560x29707) w/ labels (6 classes), and test data (640x29707). To prep the data I have 1. converted from sparse to full, ...
1
vote
2answers
1k views

Issues in pattern recognition and plots

I am trying to compare the performance of a classification result with Bayes classifier, K-NN, principal component analysis (PCA). I have doubts regarding the following (please excuse my lack of ...
2
votes
1answer
274 views

Software packages that can construct feature representation for a given text file using N-gram model

Are there any open source software packages, (Java, Matlab, R) that can generate a feature representation for a text document using N-gram model?
2
votes
1answer
100 views

Are there any simple techniques to remove/detect fluctuations during training in matlab plot?

Image below is a Matlab plot from 3-layer perceptron learning with 2 hidden nodes in both hidden layers. Are there simple technique or simple coding to remove or detect these fluctuations during ...
4
votes
1answer
1k views

Difficulty in understanding Hidden Markov Model for syntax parsing using Viterbi algorithm

I intend to apply Kevin Murphy's Hidden markov model (HMM) toolbox. I have a set of production rules(arbitrary) $A_0 \to AB [p=1]$, $A\to aC [p=1]$, $B\to bbC [p=0.5]$, $B\to b [p=0.5]$ where $A_0$ is ...