Questions tagged [weka]
WEKA is a GUI based data mining suite written in Java, developed at the University of Waikato
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How do i calculate prediction probability of a class in Java Weka Api?
I am developing a prediction model using Java Weka api. I can predict class for the new instance using the following code:
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How do I use a custom stopwords filter in the Java Weka API?
I am using the Java Weka API to build a classification model. I can use the builtin stopwords filter. However, I need to use a custom filter for my problem. I do not know how to use a custom stopwords ...
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How to use SMOTE in Java Weka API?
I am trying to build classification model using Java Weka API. My training dataset have class imbalance problems. For this reason, I want to use SMOTE to reduce class imbalance problem. But, I do not ...
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Which feature selection I should trust?
I use Python and Weka to run feature selection on my dataset (91 predictor variables). I can see a huge difference (feature ranking) from different algorithms. And these results are still quite ...
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In Weka, how to draw learning curve evaluated on both test and training set?
This is just for finding overfitting gap.
After initial research, I can only find method to draw learning curve using evaluation of test set. However, I could not evaluate on training set and over ...
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Official page of Weka for SVM java code
I am using Weka to train a model from few days. I know Weka use Java code to implement a classifier. I also heard that Weka has some github pages to describe the java code for the classifiers. I like ...
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What is the best option to test the data set of images using weka?
I have two hundred and fifty images, and extracted the features from them and put them in an Excel file, how to use the weka program so that the first 200 images for training and the remaining fifty ...
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Making fake result in data mining using weka j48 algorithm
I have 130 records in one CSV dataset and I'm using j48 decision tree. I used the whole training set for testing, and the result was 79 correctly classified and 51 incorrectly classified records.
Now! ...
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SMOTE on training data
The SMOTE could only be performed on the training data, so how can we do it using Weka? It means we have to put the training and test data in two separate files and run the SMOTE on the training file, ...
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Various algorithms performance in a problem and what can be deduced about data and problem?
HI I am currently trying to apply various algorithms to a classification problem to assess which could be better and then try to fine tune the bests of the first approach. I am a beginner so I use ...
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What can weka do that python and sklearn can't?
I would like to build a variety of classification and regression decision trees. My use case focuses on extraction and communication of decision rules. Previously weka was used in my organisation for ...
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is there any way to plot ROC curves from weka
i am using some algorithms from weka . i was willing to plot some algorithms' roc curve for comparison . Is it possible and how ?
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The Differences Between Weka Random Forest and Scikit-Learn Random Forest
I have used both weka random forest and sklearn random forest in my research, but I have realised that they use different methods to combine the predictions of the base learners i.e. decision trees to ...
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Optimum minimum number of instances in weka's j48 [closed]
There is a parameter named minnumobj in the options of the j48 tree algorithm in weka. This ...
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1
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Is there t-SNE in WEKA?
I want to use t-SNE in WEKA just for visualization purposes. I tried to look at the package manager but could not find any implementation of it.
Is there anything that I can do to achieve it?
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WEKA Random Forest and numerical attributes
I am working with Random Forests in Weka. I thought the ID3 algorithm is used to find the best split attribute at each level. But after reading a bit I noticed that ID3 can not handle numerical ...
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Where are WEKA installed packages stored
I would like to use the WEKA library in a Java program but I can't seem to find the methods I installed using WEKA's package manager.
Does anyone know where the installed methods are stored?
For ...
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WEKA Random Forest J48 Attribute Importance
I have been using WEKA to classify very long duration audio recordings. The best performing classifiers have been Random Forest and J48. The attributes used to classify the audio are acoustic indices. ...
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How to discretize a numerival value with predefined ranges in Weka?
I have imported a csv file into Weka. One of the features has a value with minimum 0 and maximum 160. Now, I want to discretise that value into three ranges as you can see below:
Less than 6 > L
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Can not run Auto WEKA [closed]
I have downloaded Auto WEKA into my computer
and installed Java Runtime Environment
and I have WIndows 10
I am trying to run the Auto WEKA by double clicking on ...
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1
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Color name prediction
Given data:
R G B Color
0 0 0 Black
255 255 255 White
255 0 0 Red
0 255 0 Lime
0 0 255 Blue
255 255 0 Yellow
0 255 255 Cyan_Aqua
...
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Method of finding threshold in Decision tree for continuous data
I am using decision tree in Weka and I have some continuous data, so when I use Weka it automatically find the threshold for me but for some reason I want to implement Decision Tree by myself so I ...
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Converting a nominal attributes to numerical ones in data set
I'm using the NSL-KDD data set which contains nominal and numerical values, and I want to convert all the nominal values to numerical ones. I tried the get_dummies ...
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How to create visualisation on medical data?
I want to create a data visualization on medical data i.e. patient's medical history, allergies one is having, any chronic patient's name must be highlighted, etc. And, there can be a separate ...
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Weka: Implementation of Random Forest
I am wondering how random forests are exactly implemented in Weka. This paper is very specific about RFs in Weka, but the description of its learning process in chapter 2 seems strange to me.
They say:...
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Correct way to take a subset of a dataset?
I am attempting a binary classification problem (using Weka). My dataset has 100,000 rows, 14 attributes (1 output variable). It takes already too long just to open the dataset in excel so I just know ...
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Multivariate analysis
Can we use weka for multivariate data analysis? When we have more than one variable as the dependent variable... ( without using factor analysis to reduce the number of variables associated with the ...
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Setting attribute weights in Weka
I'm working on feature weighting techniques (chi-square, relief..) for classification tasks using Weka. Can I add these weights to the dataset's attributes? If yes, how? Do the classification ...
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1
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different results with MEKA vs Scikit-learn!
I have a multilabel data which I've trained using different classifiers with MEKA (multilabel version of WEKA) and the evaluation results (e.g. accuracy) that MEKA gives me are different from those I ...
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Weka alternative - visual data exploration with a very large dataset
I love Weka for its visual data exploration features (it's great at quickly giving you a mile-high aerial view of the distributions of all your variables).
I have a 0.5gb dataset, and Weka is unable ...
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Attribute discretization
I have a dataset where I need to explore using unsupervised technics (clustering and association rules). What are the best strategies to discretize the numeric attributes? Also, does this (attribute ...
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How to interpret PCA rankings in Weka
I am struggling to understand what the rankings in Weka are representing. I.e. the coefficients for each attribute in the rank. What is the output in the Weka program for PCA telling me with these ...
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Analysis of Alternating Decision Tree on Weka
I am applying the AD Tree algorithm & this is the tree visualization of the output:
I can't understand the values in the decision nodes (-0.4,0.541,-0.882...), How are these calculated? & how ...
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How do I get the values of y_true and y_pred in the confusion matrix?
I am using the weka program and i want to know the values of y_true and y_pred through confusion matrix that appeared in the classification results , because I want to calculate the balanced ...
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opening Weka from command line
I'm very new to computer coding and data science in general. I'm trying to open Weka and use it on a practice csv data set called weather.arff. The manual I have says to type this into command line:
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Parameters optimization algorithms in Weka
In Weka, I used the Grid and Random search parameters tuning algorithms but unfortunately, their performance (in terms of better prediction accuracy) is observed worst when we use the ML algorithms (...
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Repeated training and testing in Weka?
I am using one file for training (e.g train.arff) and another for testing (e.g test.atff) with the 70-30 ratio in Weka. I want to ask how can I use the repeated training/testing in Weka when I have ...
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What does Make Density Based Clusterer in Weka do?
In Weka, there is a clustering algorithm with the name as Make Density Based Clusterer. When going through its properties, it takes a clusterer as base clusterer(I took it as K-means with k=3).
It ...
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1
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Attribute selection from dataset
I work on a dataset with numeric values.The class labels has also numeric values.I made the 6 numeric class labels into one witch contain values like e.g happy_pleased. I want to insert the new .arff ...
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SVM with polynomial kernel: strange results with high degree?
Currently I'm working in WEKA, using the SMO classifier (an implementation of SVM).
For an assignment I am requested to use a polynomial kernel, and report the results for degrees varying from 1 up to ...
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How to create more dimensions for data mining?
I want to analyze product sales data with WEKA. My data have attributes: sell quantity and sales price. I want to add more attributes, such as mean and standard deviation.
What formula I should use ...
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ZeroR Classifier
I've got a program that analyses some data based on a bunch of values then spits out a true/false value if it was correct or not. I'm using the Weka software to graph this all up and I just want to ...
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Sentiment Analysis algorithm in Weka
I have an assignment, i have to collect movie reviews and classify them with poz neg notr tags, and turn them info arff files. I did all of this stuff with regex etc.
But for experiment i have to ...
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Text classification with Weka (unlimited dependent variable values)
In our dataset we have 2 attributes, citizen and nric. The rule is if citizen is US, then the result should be the nric value, otherwise Non-US.
Could you please suggest which algorithm in Weka I ...
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Is my model overfitting? Weka Random Forest
I have the following result from weka. As I observed the result I have noticed the ROC area is above 90 and the correctly classified instances is 85% Is this a sign of overfitting?
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I need help in PCA results using WEKA Tool [closed]
I'm working on an experiment using KDD'99 cupset I have 42 features. the paper I 'm comparing with concludes that 3 features with precision ..% ok are the best subset to identify the attack X.
In my ...
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Increasing minNumObj increasing accuracy in decision tree
I have been using a J48 classifier in weka and have noticed that increasing
minNumObj -- The minimum number of instances per leaf leads to a small accuracy increase.
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Weka Character Level CNN
I am wanting to use a character level CNN to classify a heap of documents based on the century which they are from. I am having difficulties finding any resources on how to do character level ...
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627
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Remove attributes with missing values exceeding a given threshold in WEKA
I imported csv file into WEKA, i have features that have missing value that has missing value percentage of 70% or above, i want to remove these features by weka or also sort that features by missing ...
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Processed data cannot build Naive Bayes Classifier model
Having preprocessed data using weka supervised cfssubseteval forward and backward selection, the decision tree model builds and makes prediction well, but naive Bayes do not recognize the same Arff ...
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