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Cross validation in matlab
The Statistics Toolbox provides utilities for cross-validation. If you are using R2011a or later, take a look at |Classification...

oltre 13 anni fa | 0

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Create an ROC Curve From Binary Classification Data
From |perfcurve| doc: *[X,Y] = perfcurve(labels,scores,posclass) computes a ROC curve for a vector of classifier predictions ...

oltre 13 anni fa | 1

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Viewing the tree used for prediction by the method of "RUSBoost' in fitensemble
The strong learner is the ensemble. An ensemble is a collection of trees. It predicts by averaging predictions from individual t...

oltre 13 anni fa | 1

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SVM classification with different kernels
See this thread <http://www.mathworks.com/matlabcentral/answers/57232-how-to-use-svmtrain-with-a-custom-kernel-in-matlab>

oltre 13 anni fa | 0

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Two linear discriminant functions to classify objects
I don't understand your question. But perhaps the following will help. In 2011b, we shipped |ClassificationDiscriminant| class w...

oltre 13 anni fa | 0

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How to use svmtrain() with a custom kernel in Matlab?
By convention adopted for |svmtrain|, observations are in rows and predictors are in columns. The same convention would hold for...

oltre 13 anni fa | 0

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[Compute AUC of a ROC Function]
If you have Statistics Toolbox, the |perfcurve| function can compute AUC. You mention that you have 3 classes. I am guessing ...

oltre 13 anni fa | 0

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Use of penalty multiplier C (boxconstraint) in svmtrain
Off hand I cannot think of a reason why you couldn't use |quadprog| to solve the 1-norm problem. I don't know why the 2-norm sol...

oltre 13 anni fa | 0

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Use of penalty multiplier C (boxconstraint) in svmtrain
The magnitude of the margin slack vector can be shrunk using a 1-norm or 2-norm penalty. The 1-norm version seems more popular, ...

oltre 13 anni fa | 0

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Is there an LDA method that matches the format "D_t= W_Tc^T * E_t + w_0"
Sounds like you want a linear regression model: <http://www.mathworks.com/help/stats/linear-regression-model-workflow.html> ...

oltre 13 anni fa | 0

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hand gesture data classification and recognize gesture from image
Perhaps you could start by reading the User Guide for the Statistics Toolbox, where many tools for classification are collected:...

oltre 13 anni fa | 0

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model learning in the presence of noise
When you say "classifier ensemble", I assume you mean "decision tree ensemble". The time it takes to grow a tree depends on the ...

quasi 14 anni fa | 0

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How to run a chi-square test?
|chi2gof| tells you how closely the observed distribution resembles your theoretical guess. You don't have a distribution yet. T...

quasi 14 anni fa | 0

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Results of bootci and bootstrp funciton don't match.
You will get a better match to your quantile results if you run ci=bootci(1000, {@var, data}, 'type', 'per') Take a look...

quasi 14 anni fa | 0

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Classregtree with multiple dependent variables
Your title says "multiple dependent variables", and your question says "a set of independent variables". Do you have multiple de...

quasi 14 anni fa | 0

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Algorithms for imbalanced multi class classification in Matlab?
I described approaches for learning on imbalanced data here <http://www.mathworks.com/matlabcentral/answers/11549-leraning-class...

quasi 14 anni fa | 4

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How can I use LDA (Linear or Fisher Discrimnant Analysis) with an hardwritten digits dataset (like MNIST or USPS)?
I am not an expert in image analysis, but it seems you misunderstand what you need to do. LDA uses matrix X in which rows are ob...

quasi 14 anni fa | 1

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How to report Terminal Node (only the one use to predict Y) Standard Deviation in TreeBagger?
TreeBagger is an ensemble of trees. All trees are different because they were grown on different bootstrap replicas of the data....

quasi 14 anni fa | 0

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Sharing of a trained SVM model
There is no unified "SVM format" shared by different implementations. You can always dump the svmstruct to an ascii file and hop...

quasi 14 anni fa | 0

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What is a good Dimensionality Reduction technique I can use?
Your best chance would be to set up variable selection based on that linear classifier you are using (you don't say what it is)....

quasi 14 anni fa | 0

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Determining variables that contribute to principal components
The first paragraph in the doc description for princomp says "COEFF is a p-by-p matrix, each column containing coefficients for ...

quasi 14 anni fa | 0

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How to find the important features from many features of a MFFC speech sample??
I described feature ranking/selection tools available from Statistics Tlbx here: <http://www.mathworks.com/matlabcentral/answers...

quasi 14 anni fa | 0

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Select machine learning features in Matlab
Here are Statistics Toolbox utilities you should look into: # sequentialfs # relieff # predictorImportance method of Classi...

quasi 14 anni fa | 1

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fitensemble adaboost m1 stump picking
A decision tree in a boosting ensemble by default minimizes the Gini diversity index, not classification error. Two child nodes ...

quasi 14 anni fa | 0

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How to best determine the probability of a distribution given an outlying observation?
If you know the reference distribution analytically, you can compute its cdf at the smallest observed value. Suppose this cdf va...

quasi 14 anni fa | 0

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fitensemble with adaboost and trees
http://www.mathworks.com/help/toolbox/stats/classificationensembleclass.html http://www.mathworks.com/help/toolbox/stats/comp...

quasi 14 anni fa | 0

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Question about KNN and how to use it.
Take a look at the User Guide for k-NN classification: http://www.mathworks.com/help/toolbox/stats/bsehyju-1.html In your cas...

quasi 14 anni fa | 0

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Why covariance matrix is computed like this?
m-1 in the denominator gives the unbiased estimate, and m gives the max likelihood estimate. http://en.wikipedia.org/wiki/Est...

quasi 14 anni fa | 0

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Matlab TreeBagger Cost argument not working as it works with similar function fitensemble
fitensemble and TreeBagger use different approaches to incorporate the cost matrix. fitensemble uses the cost matrix to updat...

circa 14 anni fa | 0

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Help using perfcurve function!!
Other than a few typos (for example, y1 = (1:132)'>70; clearly is not what you meant), I don't see anything wrong with your code...

circa 14 anni fa | 0

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