Statistical Analysis Stack Exchange
Statistical Analysis Stack Exchange

Questions tagged [e1071]

e1071 is a R package for miscellaneous functions of the Department of Statistics (e1071) at TU Wien (Vienna University of Technology). It includes functions for latent class analysis, short time Fourier transform, fuzzy clustering, support vector machines, shortest path computation, bagged clustering, naive Bayes classifier, etc.

48 questions
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Problem with e1071 libsvm?

I have a dataset with two overlapping classes, seven points in each class, points are in two-dimensional space. In R, and I'm running svm from the e1071 package to build a separating hyperplane for these classes. I'm using the following…
Leo
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How to obtain decision boundaries from linear SVM in R?

I am in need of a package that can give me the equation for a linear SVM model. Currently I'm using e1071 like so: library(e1071) m = svm(data, labels, type='C', kernel='linear', cost=cost, probability=FALSE, scale=scale) w = t(m$coefs) %*%…
reisner
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Difference between the types of SVM

I am new to support vector machines. Short explanation The svm function from the e1071 package in R offers various options: C-classification nu-classification one-classification (for novelty detection) eps-regression nu-regression What are the…
Ferdi
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Improving the SVM classification of diabetes

I am using SVM to predict diabetes. I am using the BRFSS data set for this purpose. The data set has the dimensions of $432607 \times 136$ and is skewed. The percentage of Ys in the target variable is $11\%$ while the Ns constitute the remaining…
Anand
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Meaning of Epsilon in SVM regression

I did some tutorials and read few articles but still have a problem with SVM, exactly with SVR. I'm doing analysis in R and I use e1071 library with "svm" function. Into that function I use my multivariable equation, so svm works since now like…
boplight
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Suitable number of classes for SVM in text categorization

I'm doing text categorization with R and SVM in the package e1071. I have around 30000 text files for training, and 10000 for test. The goal is to hierarchically categorize these files. For example, I have 13 categories in level 1, such as sports,…
Ensom Hodder
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SVM predicts everything in one class

I'm running a basic language classification task. There are two classes (0/1), and they are roughly evenly balanced (689/776). Thus far, I've only created basic unigram language models and used these as the features. The document term matrix, before…
triddle
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Do we have to fix splits before 10-folds cross validation if we want to compare different algorithms?

I work with R and let's say that I have a train set and a test set. I want to test different algorithms (for example neural networks and svm). I will perform a first 10-folds cross validation on my train set for tuning the neural network. Then I…
Stéphanie C
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R caret Naive Bayes (untuned) results differ from klaR

I'm running a naive bayes classification model and I noticed that the caret package returns a different result than does klaR (which caret references) or e1071. My question is: is there something I'm doing wrong with my caret syntax that I'm not…
msheffer
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5
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Spam filtering using naive Bayesian classifiers with the e1071/klaR package on R

I'm looking at doing text classification/spam filtering using naive Bayesian classifiers with the e1071 or klaR package on R. Is there a good tutorial out there to describe this? I'm kind of stuck because I'm not sure what to use as the data to…
Sau Sheong
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Methods to combine ( e1071 svm ) models in R to generate a more complete, accurate model

I am using the function svm from the package e1071 in R to generate a support vector machine model. I have a very large data set, and for the moment, while in an exploratory mode, want to simply read in small slices of the data that can be modeled…
Mike Williamson
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How to draw plot of the values of decision function of multi class svm versus another arbitrary values?

I am trying to draw a plot of the decision function ($f(x)=sign(wx+b)$ which can be obtain by fit$decision.values in R using the svm function of e1071 package) versus another arbitrary values. From svm documentation, for binary classification the…
user2802663
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SVM in R (package e1071): predicting class using predict()

I have difficulties to understand predict.svm. Please find an illustration of my confusion below. As we can see, results are different depending on the probability argument of predict(). So my question is: what is the difference between…
user7064
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SVM prediction accuracy drops when using Test data

I am using the Kaggle Scikit data to learn R. I am using the R e1071 SVM function to predict classes. When I use: svm(train, trainLabels, scale = TRUE, type = NULL, kernel = "polynomial") I obtain this level of accuracy on a sample of the Train…
Timothée HENRY
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Recover $\rho$ of $\nu$-SVM from e1071 package in R

Given a dataset $\{(x_i,y_i)\}_{i=1}^n$, the primal problem for $\nu$-SVM is: \begin{align} &\min_{w,b,\xi,\rho} && \frac{1}{2}w^\top w-\nu\rho+\frac{1}{n}\sum_{i=1}^n\xi_i\\ &\text{subject to} && y_i(w^\top x_i+b)\geq\rho-\xi_i,\\ & …
Francis
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