graphical model of LDA

lda_graphical_model.tex

\documentclass[a4j,12pt,dvipdfmx]{jsarticle}
\usepackage{tikz}
\usepackage[dvipdfmx]{hyperref}
\usetikzlibrary{positioning,fit,arrows.meta}

\begin{document}
  \begin{tikzpicture}
    \node[draw,circle,minimum size=1cm] (alpha) {$\alpha$};
    \node[draw,circle,minimum size=1cm, right=1cm of alpha] (theta) {$\theta_d$};
    \node[draw,circle,minimum size=1cm, right=1cm of theta] (z) {$z_{d,i}$};
    \node[draw,fill=gray!60,circle,minimum size=1cm, right=1cm of z] (omega) {$\omega_{d,i}$};
    \node[draw,circle,minimum size=1cm, right=1cm of omega] (phi) {$\phi_k$};
    \node[draw,circle,minimum size=1cm, right=1cm of phi] (beta) {$\beta$};
    
    \draw[-Stealth] 
        (alpha) edge (theta)
        (theta) edge (z)
        (z) edge (omega)
        (phi) edge (omega)
        (beta) edge (phi);

    \node[inner sep=0cm,fit={(phi)}] (wrap_phi) {};
    \node[inner sep=0cm,below=0.1cm of wrap_phi.south east,anchor=east] (caption_K) {$K$};
    \node[draw,rounded corners,fit={(wrap_phi)(caption_K)}] (plate_phi) {};

    \node[inner sep=0cm,fit={(z)(omega)}] (wrap_z_omega) {};
    \node[inner sep=0cm,below=0.2cm of wrap_z_omega.south east,anchor=east] (caption_n) {$n_d$};
    \node[draw,rounded corners,fit={(wrap_z_omega)(caption_n)}] (plate_z_omega) {};

    \node[inner sep=0cm,fit={(theta)(plate_z_omega)}] (wrap_theta_z_omega) {};
    \node[inner sep=0cm,below=0.2cm of wrap_theta_z_omega.south east,anchor=east] (caption_M) {$M$};
    \node[draw,rounded corners,fit={(wrap_theta_z_omega)(caption_M)}] (plate_theta_z_omega) {};
  \end{tikzpicture}
\end{document}