\begin{tikzpicture}

    \def \h{4}

    %Pipeline
    \node[rectangle,draw=red] (s) at (2*\h,0) {Sensitive attribute};
    \node[rectangle,draw=blue] (inf) at (0,0) {Classification};
    \node[rectangle,draw=blue] (att) at (\h,0) {Attack};
    \draw[->,color=blue] (inf) to (att);
    \draw[->,color=red] (att) to (s);

    %Ensembles
    \node (c0) at (0,1) {$0$};
    \node (c1) at (0,2) {$1$};
    \node (c2) at (0,3) {$2$};
    \node (c3) at (0,4) {$\vdots$};
    
    \node (a0) at (2*\h,1) {$853$};
    \node (a1) at (2*\h,2) {$22$};
    \node (a2) at (2*\h,3) {$312$};
    \node (a3) at (2*\h,4) {$\vdots$};

    \draw[->] (c0) to (a0);
    \draw[->] (c1) to (a1);
    \draw[->] (c2) to (a2);
    \draw[->] (c3) to (a3);



\end{tikzpicture}