[003] Tips

$\textbf{y}_{n\times 1}=X_{n\times p}\boldsymbol\beta_{p\times 1}+\boldsymbol\epsilon_{n\times 1}$

TIPS $\LaTeX$
$ \$ $\textbf{y}_{p\times 1} =
X_{n\times p}\boldsymbol\beta_{p\times 1} +
\boldsymbol\epsilon_{n\times 1}$ \$ $

TIPS HTML
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