begin{align}
f(beta_i^{r,c},alpha_{r,c} mid n_{r,i},t_{c,i},(lambda_1,lambda_2) text{ or } lambda) propto \
times prod_{i=1}^{P} prod_{c=1}^C ({theta_{c,i}})^{t_{c,i}} &;;bigg] textbf{Individualdaten}\
times prod_{i=1}^{P} prod_{r=1}^R frac{1}{B(alpha)} prod_{c=1}^C (beta_i^{r,c})^{alpha^{r,c}-1} &;;bigg] textbf{Priori Distribution}\
times prod_{r=1}^{R} prod_{c=1}^C frac{1}{lambda_2 ^{lambda_1} Gamma(lambda_1)} alpha_{r,c}^{lambda_1-1} exp(-alpha_{r,c} lambda_2) &;;
tikzmarknode{brkt}{bigg]}
tikzmarknode{above}{textbf{Priori Distribution}}\
text{or}\
tikzmarknode{l1}{times prod_{r=1}^{R} prod_{c=1}^C lambda
exp(-lambdaalpha_{r,c}}
&\
tikzmarknode{l2}{text{with } B(alpha)=frac{prod_{c'=1}^C
Gamma(alpha_{rc'})}{Gamma(Sigma_{c'=1}^Calpha_{r,c'})}}
end{align}
begin{tikzpicture}[overlay,remember picture]
draw[line width=0.6pt] (brkt.west |- l1.north) -| (brkt.north |- l2.south)
node[pos=0.75,right]{textbf{Priori Distribution}}
-- (brkt.west |- l2.south);
end{tikzpicture}

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<argument> ...knode {brkt}{bigg ]} tikzmarknode
{above}{textbf {Priori Di...
l.343 end{align}