s for the causal effects $\documentclass[00pt]{minimal}                 \usepackage{amsmath}                 \usepackage{wasysym}                  \usepackage{amsfonts}                  \usepackage{amssymb}                  \usepackage{amsbsy}                 \usepackage{mathrsfs}                 \usepackage{upgreek}                 \setlength{\oddsidemargin}{-00pt}                 \begin{document}$${\hat{{\boldsymbol{\theta }}}}_{{\boldsymbol{\gamma }}}$$\end{document}$ of model $\documentclass[00pt]{minimal}                 \usepackage{amsmath}                 \usepackage{wasysym}                  \usepackage{amsfonts}                  \usepackage{amssymb}                  \usepackage{amsbsy}                 \usepackage{mathrsfs}                 \usepackage{upgreek}                 \setlength{\oddsidemargin}{-00pt}                 \begin{document}$${M}_{{\boldsymbol{\gamma }}}$$\end{document}$ as$$\documentclass[00pt]{minimal}                 \usepackage{amsmath}                 \usepackage{wasysym}                  \usepackage{amsfonts}                  \usepackage{amssymb}                  \usepackage{amsbsy}                 \usepackage{mathrsfs}                 \usepackage{upgreek}                 \setlength{\oddsidemargin}{-00pt}                 \begin{document}$${\hat{{\boldsymbol{\theta }}}}_{{\boldsymbol{\gamma }}}={\mathbf{\Omega }}{{\boldsymbol{\beta }}}_{{{\bf{X}}}_{{\boldsymbol{\gamma }}}} ^{t}{{\boldsymbol{\beta }}}_{{\bf{Y}}}={({{\boldsymbol{\nu }}}_{{\boldsymbol{\gamma }}}^{-0}+{{\boldsymbol{\beta }}}_{{{\bf{X}}}_{{\boldsymbol{\gamma }}}} ^{t}{{\boldsymbol{\beta }}}_{{{\bf{X}}}_{{\boldsymbol{\gamma }}}})}^{-0}{{\boldsymbol{\beta }}}_{{{\bf{X}}}_{{\boldsymbol{\gamma }}}} ^{t}{{\boldsymbol{\beta }}}_{{\bf{Y}}}