2.1 Decision Tree

Code

graph TD;
    N0["‘Viagra’"] -->|"=0"| N11["‘lottery’"];
    N0 -->|"=1"| L3["ĉ(x)=spam"]:::filled;
    N11 -->|"=0"| L1["ĉ(x)=ham"]:::filled;
    N11 -->|"=1"| L2["ĉ(x)=spam"]:::filled;

    classDef filled fill:#cccccc,stroke:#000,color:#000;
    class L1,L2,L3 filled;

graph TD;
    N0["‘Viagra’"] -->|"=0"| N11["‘lottery’"];
    N0 -->|"=1"| L3["ĉ(x)=spam"]:::filled;
    N11 -->|"=0"| L1["ĉ(x)=ham"]:::filled;
    N11 -->|"=1"| L2["ĉ(x)=spam"]:::filled;

    classDef filled fill:#cccccc,stroke:#000,color:#000;
    class L1,L2,L3 filled;