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How to find the optimal tree size when building a decision tree?
Grow a deep tree by setting minparent to 1, find the optimal pruning level using http://www.mathworks.com/help/toolbox/stats/...

fast 14 Jahre vor | 0

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Cart Algorithm in Matlab with more than binary splits?
The CART algorithm described in the book by Breiman et al. uses binary splits only. The MATLAB implementation is based on this a...

etwa 14 Jahre vor | 0

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Crossvalidation: anonymous function handle with toolbox classifiers
I think you've hit a bug in the crossval function. My guess is that classRF_predict returns numeric labels, and crossval does no...

etwa 14 Jahre vor | 1

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Crossvalidation: anonymous function handle with toolbox classifiers
I am not an expert on the randomforest-matlab package, so my advice could be off. I find two things in your post worth investiga...

etwa 14 Jahre vor | 0

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c4.5
I don't know if you can use classregtree for "c4.5 classification". If you are looking for *a* decision tree implementation, you...

etwa 14 Jahre vor | 0

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Leave-one-out cross-validation with svmtrain gives 'impossible' accuracy results
You are missing my point about the majority class. Let me try again. Suppose you generate 200 observations and assign labels ...

etwa 14 Jahre vor | 1

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c4.5
Statistics Toolbox provides a decision tree implementation based on the book Classification and Regression Trees by Breiman et a...

etwa 14 Jahre vor | 1

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Leave-one-out cross-validation with svmtrain gives 'impossible' accuracy results
I don't know what went wrong with your real data. In this mock-up exercise, you are trying to separate two classes that are esse...

etwa 14 Jahre vor | 0

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edit-error in classifier
Quoting http://www.mathworks.com/matlabcentral/answers/34771-classifier In particular, 2nd example for crossval here http://w...

etwa 14 Jahre vor | 0

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error using classperf
See my response in http://www.mathworks.com/matlabcentral/answers/34771-classifier In your code snippet, the error is caused ...

etwa 14 Jahre vor | 0

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-(Face clssification using Random Forest Technique),,,theri one problem occured during the use of Random-Forest MATLAB code,,,,,
1. ytrain and ytest are likely arrays of true class labels (if you have a classification problem) or arrays of observed continuo...

etwa 14 Jahre vor | 0

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classifier
You can use out-of-bag error as an unbiased estimate of the generalization error. Train TreeBagger with 'oobpred' set to 'on' an...

etwa 14 Jahre vor | 0

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classifier
If you have Statistics Toolbox and MATLAB 9a or later, you can use TreeBagger. Please read the documentation and take a look at ...

etwa 14 Jahre vor | 0

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error using svmtrain (not enough inputs)
If you are using svmtrain function from the official MATLAB install (verify by typing 'which svmtrain' in your command window), ...

etwa 14 Jahre vor | 0

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does RegressionTree.fit see the predictors as nominal variables or ordinal variables if you set 'CategoricalPredictors' to 'all'?
For trees, "categorical predictor" means "nominal predictor". If you had an ordinal predictor, you could just use it as is becau...

etwa 14 Jahre vor | 0

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How do I display the rule in a regression tree in a different fashion than default?
You do not say what regression tree you are using. Let's assume you are using RegressionTree. It is not clear what you mean ...

etwa 14 Jahre vor | 0

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How do you obtain a vector of predicted classes generated after cross-valiation of a decision tree?
If you have 11a or later, you can use ClassificationTree: load fisheriris; cvtree = ClassificationTree(meas,species,'kfo...

etwa 14 Jahre vor | 0

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How to classify using non-linear support vector machine
svmStruct = svmtrain(data(train,:),groups(train),'kernel_function','rbf')

etwa 14 Jahre vor | 0

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Machine Learning Confidence Value question
The 3rd output from CLASSIFY is class posterior probabilities. Isn't this what you want?

etwa 14 Jahre vor | 0

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Is possible to accelerate sequentialfs using a GPU?
TreeBagger and sequentialfs can be run in a parallel mode using parfor. See 'help parallelstats' for more info. Executing these ...

etwa 14 Jahre vor | 0

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Remove or replace trees from a TreeBagger ensemble
Combining two objects would be hard. You can work around this by growing one big ensemble and treating parts of it as separate e...

etwa 14 Jahre vor | 1

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Beantwortet
Why does sequentialfs always outperform cross-validation with selected features?
I don't know if your code is correct. But accuracy estimates obtained by sequential selection are always biased high. Consid...

mehr als 14 Jahre vor | 0

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predict function behavior in Matlab regression trees
It's the average over observations in the node.

mehr als 14 Jahre vor | 0

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what's the difference between DeltaCritDecisionSplit property vs. Gini's Diversity Index?
Predictor importance estimates for every tree in an ensemble are added together. The sum is then divided by the number of trees....

mehr als 14 Jahre vor | 0

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what's the difference between DeltaCritDecisionSplit property vs. Gini's Diversity Index?
Yes, DeltaCritDecisionSplit property of TreeBagger is the equivalent of predictorImportance method for an ensemble produced by f...

mehr als 14 Jahre vor | 0

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classregtree.m- how to get the node and leaf details
Here is online doc for classregtree methods: http://www.mathworks.com/help/toolbox/stats/classregtreeclass.html Or you can...

mehr als 14 Jahre vor | 0

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How to save generated tree from classregtree function into array variable
Your t variable contains much more than these 9 lines. It is an object with a whole bunch of methods. The output you see is just...

mehr als 14 Jahre vor | 0

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Classification by logistic regression
Because logistic regression is a simple linear model and because you have 10 times as many observations as predictors, the class...

mehr als 14 Jahre vor | 0

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decision tree const. prob.
Depends on what you mean by "code of the tree". If you want to find classregtree code in your MATLAB install, type 'which cla...

mehr als 14 Jahre vor | 0

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Test the performance of the ClassificationTree algorithm against the excel file data
Yes, it is possible. Follow MATLAB documentation for reading data from an Excel file and estimating the tree accuracy. If you ar...

mehr als 14 Jahre vor | 0

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