Top "Classification" questions

In machine learning and statistics, classification is the problem of identifying which of a set of categories a new observation belongs to, on the basis of a training set of data containing observations whose category membership (label) is known.

Best way to combine probabilistic classifiers in scikit-learn

I have a logistic regression and a random forest and I'd like to combine them (ensemble) for the final classification …

python machine-learning classification scikit-learn
Why is the F-Measure a harmonic mean and not an arithmetic mean of the Precision and Recall measures?

When we calculate the F-Measure considering both Precision and Recall, we take the harmonic mean of the two measures instead …

machine-learning classification data-mining
Predicting how long an scikit-learn classification will take to run

Is there a way to predict how long it will take to run a classifier from sci-kit learn based on …

python machine-learning classification scikit-learn
Sentiment analysis with NLTK python for sentences using sample data or webservice?

I am embarking upon a NLP project for sentiment analysis. I have successfully installed NLTK for python (seems like a …

nlp nltk weka classification
One-class classification with SVM in R

I'm using the package e1071 in R in order to build a one-class SVM model. I don't know how to …

r classification svm libsvm
How to split data (raw text) into test/train sets with scikit crossvalidation module?

I have a large corpus of opinions (2500) in raw text. I would like to use scikit-learn library to split them …

machine-learning scikit-learn classification cross-validation text-classification
How can I build a model to distinguish tweets about Apple (Inc.) from tweets about apple (fruit)?

See below for 50 tweets about "apple." I have hand labeled the positive matches about Apple Inc. They are marked as 1 …

java python r machine-learning classification
Basic text classification with Weka in Java

Im trying to build a text classifier in JAVA with Weka. I have read some tutorials, and I´m trying …

java classification weka document-classification
How to create a dendrogram with colored branches?

I would like to create a dendrogram in R which has colored branches, like the one shown below. So far …

r classification dendrogram dendextend
ROC curve in R using rpart package?

I split Train data set and Test data set. I used a package rpart for CART (classification tree) in R (…

r classification predict roc