# [Tex/LaTex] Math mode expected value

fontsmath-mode

I have a question about my expected value symbol in my latex document.
When I use \mathbb{E}, it actually gives me this:

rather than this:

Can someone explain this to me please, because I prefer the second symbol, it's more common in the literature than the first one.

You don't need to load bbold just for one of its symbols.

\documentclass{article}
\usepackage{amsmath,amssymb}

\DeclareRobustCommand{\bbone}{\text{\usefont{U}{bbold}{m}{n}1}}

\DeclareMathOperator{\EX}{\mathbb{E}}% expected value

\begin{document}

$\EX(f)+\bbone$

\end{document}