2.  A collection of open source ML algorithms ◦ pre-processing ◦ classifiers ◦ clustering ◦ association rule  Created by researchers at the University of Waikato in New Zealand  Java based

3.  Download software from http://www.cs.waikato.ac.nz/ml/weka/downlo ading.html ◦ Several options for windows, mac or linux ◦ X86 (for 32-bit processors), x64( for 64-bit)

4. WEKA:: Interface

5.  Uses flat text files to describe the data  Can work with a wide variety of data files including its own “.arff” format and C4.5 file formats  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)

6. @relation heart-disease-simplified @attribute age numeric @attribute sex { female, male} @attribute chest_pain_type { typ_angina, asympt, non_anginal, atyp_angina} @attribute cholesterol numeric @attribute exercise_induced_angina { no, yes} @attribute class { present, not_present} @data 63,male,typ_angina,233,no,not_present 67,male,asympt,286,yes,present 67,male,asympt,229,yes,present 38,female,non_anginal,?,no,not_present... A more thorough description is available here http://www.cs.waikato.ac.nz/~ml/weka/ar ff.html http://www.cs.waikato.ac.nz/~ml/weka/ar ff.html