TeX source:

\left\{ \begin{array} {ll} d_{Tr,t}=αd_{Tr,t−1}(a+\overline{a}−cT_r−2b_{11}d_{Tr,t−1}−b_{12}d_{Or,t−1})+d_{Tr,t−1}+τεT_r,t \\ d_{Or,t} = βd_{Or,t−1}(a−cO_r+θ(\overline {φ} φ)−b_{21}d_{Tr,t−1}−2b_{22}d_{Or,t−1})(1−φ)+d_{Or,t−1}+K(d_{Or,t−1}−d_{Or,t})+τεO_r,t \end{array} \right.