Algorithm 4: Wrapper based Sequential Backward Selection of Feature FS Algorithm.

1 Algorithm starting with $k=d$, the d is dimensional of feature full space $X_d$

2 Eliminate feature $x^{-}$, that maximizes the criterion:

3$X^{-}=argmax(X_k-x)$, Where $x\in X_k$

4 Eliminate feature $x^{-}$ from feature space:

5$X_k-1=X_k-X^{-}$

6$k=k-1$

7 Finish if k reached the required features, if not then repeat step 2