For SNP j and focal trait f, we have \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\widehat {\bf{b}}_{{\mathrm{OLS}}}$$\end{document}b^OLS values for k traits, and we wish to obtain the index weights, wj,k, for each \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\widehat {\bf{b}}_{{\mathrm{OLS}}_{j,k}}$$\end{document}b^OLSj,k effect as:23\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\widehat {\bf{b}}_{{\mathrm{wMT}} - {\mathrm{OLS}}_{j,f}} = \mathop {\sum }\limits_k w_{j,k}{\hat{\bf b}}_{{\mathrm{OLS}}_{j,k}} = {\bf{w}}_j\prime \widehat {\bf{b}}_{{\mathrm{OLS}}_j}$$\end{document}b^wMT-OLSj,f= ∑kwj,kb^OLSj,k=wj′b^OLSj