\\documentclass[11pt,a4paper,twoside]{article}
 \\usepackage[a4paper,top=2.5cm,bottom=2cm,left=2.5cm,right=2.5cm]{geometry}
 \\usepackage[utf8]{inputenc}
-\\usepackage{amsmath}
-\\usepackage{amssymb}
+\\usepackage{amsmath,amssymb,dsfont}
 \\usepackage[pdftex]{graphicx}
 \\usepackage[colorlinks=true,linkcolor=blue,urlcolor=blue,citecolor=blue]{hyperref}
 \\usepackage{tikz}
 
 \\def\\argmax{\\operatornamewithlimits{argmax}}
 \\def\\argmin{\\operatornamewithlimits{argmin}}
+\\def\\expect{\\mathds{E}}
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %% The \\todo command