Example of a decision Tree Splitting Attributes Tid Refund Marital Taxable Status Income Cheat 1 Y Single 125K No 2No Married 100K No Refund Yes 3No Single 70K No 4 Yes Married 120K No NO MarT 5No Divorced 95K Yes Single, DiVorced Married nO Married60K No 7 Y Divorced220K No TaxIng NO 8No Yes <80K >80K No Married 75K No NO YES 10No Single 90K Yes Training Data Model: decision tree C Tan, Steinbach, Kumar Introduction to Data Mining 4/18/2004
© Tan,Steinbach, Kumar Introduction to Data Mining 4/18/2004 ‹#› Example of a Decision Tree Tid Refund Marital Status Taxable Income Cheat 1 Yes Single 125K No 2 No Married 100K No 3 No Single 70K No 4 Yes Married 120K No 5 No Divorced 95K Yes 6 No Married 60K No 7 Yes Divorced 220K No 8 No Single 85K Yes 9 No Married 75K No 10 No Single 90K Yes 10 Refund MarSt TaxInc NO YES NO NO Yes No Single, Divorced Married < 80K > 80K Splitting Attributes Training Data Model: Decision Tree
Another Example of Decision Tree MasT Single Married Divorced d refund marital Taxable Status Income Cheat NO Refund Single 125K No Yes No Married 100K No 3No Single 70K No NO TaxIne Married 120K No <80K >80K 5No Divorced 95K Yes NO YES 6No Married 60K No Divorced 220K No 8No 85K Yes 9No Married 75K No There could be more than one tree that 10No Single 90KYes fits the same datal C Tan, Steinbach, Kumar Introduction to Data Mining 4/18/2004
© Tan,Steinbach, Kumar Introduction to Data Mining 4/18/2004 ‹#› Another Example of Decision Tree Tid Refund Marital Status Taxable Income Cheat 1 Yes Single 125K No 2 No Married 100K No 3 No Single 70K No 4 Yes Married 120K No 5 No Divorced 95K Yes 6 No Married 60K No 7 Yes Divorced 220K No 8 No Single 85K Yes 9 No Married 75K No 10 No Single 90K Yes 10 MarSt Refund TaxInc NO YES NO NO Yes No Married Single, Divorced < 80K > 80K There could be more than one tree that fits the same data!
Decision tree classification task Tree Tid Attrib1 Attrib2 Attrib3 Class Induction algorith Medium Induction Large 220K Learn Model 90K Training set Model Decision Model ree Attrib3 Cla Deduction 95K C Tan, Steinbach, Kumar Introduction to Data Mining 18/2004
© Tan,Steinbach, Kumar Introduction to Data Mining 4/18/2004 ‹#› Decision Tree Classification Task Apply Model Induction Deduction Learn Model Model Tid Attrib1 Attrib2 Attrib3 Class 1 Yes Large 125K No 2 No Medium 100K No 3 No Small 70K No 4 Yes Medium 120K No 5 No Large 95K Yes 6 No Medium 60K No 7 Yes Large 220K No 8 No Small 85K Yes 9 No Medium 75K No 10 No Small 90K Yes 10 Tid Attrib1 Attrib2 Attrib3 Class 11 No Small 55K ? 12 Yes Medium 80K ? 13 Yes Large 110K ? 14 No Small 95K ? 15 No Large 67K ? 10 Test Set Tree Induction algorithm Training Set Decision Tree
Apply Model to Test Data Test Data Start from the root of tree Refund marital Taxable Status Income Cheat No Married 80K Refund Yes NO MasT Single, Diorced Married TaxIng NO 80K >80K NO YES C Tan, Steinbach, Kumar Introduction to Data Mining 18/2004
© Tan,Steinbach, Kumar Introduction to Data Mining 4/18/2004 ‹#› Apply Model to Test Data Refund MarSt TaxInc NO YES NO NO Yes No Single, Divorced Married < 80K > 80K Refund Marital Status Taxable Income Cheat No Married 80K ? 10 Test Data Start from the root of tree
Apply Model to Test Data Test Data Refund marital Taxable Status Income Cheat No Married 80K Refund Yes NO MasT Single, Diorced Married TaxIng NO 80K >80K NO YES C Tan, Steinbach, Kumar Introduction to Data Mining 18/2004
© Tan,Steinbach, Kumar Introduction to Data Mining 4/18/2004 ‹#› Apply Model to Test Data Refund MarSt TaxInc NO YES NO NO Yes No Single, Divorced Married < 80K > 80K Refund Marital Status Taxable Income Cheat No Married 80K ? 10 Test Data