Download WEKA: the software

Preprocessing with WEKA
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WEKA: the software
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Machine learning/data mining software written in
Java (distributed under the GNU Public License)
Used for research, education, and applications
Complements “Data Mining” by Witten & Frank
Main features:
Comprehensive set of data pre-processing tools,
learning algorithms and evaluation methods
 Graphical user interfaces (incl. data visualization)
 Environment for comparing learning algorithms
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WEKA only deals with “flat” files
@relation iris
@attribute sepallength real
@attribute sepalwidth real
@attribute petallength real
@attribute petallength real
@attribute petalwidth real
@attribute class { Iris-setosa, Iris-versicolor, Iris-virginica}
@data
4.6,3.2,1.4,0.2,Iris-setosa
5.3,3.7,1.5,0.2,Iris-setosa
7.0,3.2,4.7,1.4,Iris-versicolor
6.3,3.3,6.0,2.5,Iris-virginica
6.3,2.9,5.6,1.8,Iris-virginica
...
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WEKA only deals with “flat” files
@relation iris
@attribute sepallength real
@attribute sepalwidth real
@attribute petallength real
@attribute petallength real
@attribute petalwidth real
@attribute class { Iris-setosa, Iris-versicolor, Iris-virginica}
@data
4.6,3.2,1.4,0.2,Iris-setosa
5.3,3.7,1.5,0.2,Iris-setosa
7.0,3.2,4.7,1.4,Iris-versicolor
6.3,3.3,6.0,2.5,Iris-virginica
6.3,2.9,5.6,1.8,Iris-virginica...
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Explorer: pre-processing the data
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Data can be imported from a file in various
formats: ARFF, CSV, C4.5, binary
Data can also be read from a URL or from an SQL
database (using JDBC)
Pre-processing tools in WEKA are called “filters”
WEKA contains filters for:
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Discretization, normalization, resampling, attribute
selection, transforming and combining attributes, …
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Conclusion: try it yourself!
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WEKA is available at
http://www.cs.waikato.ac.nz/ml/weka
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