series of Equations

The Latex code is

\begin{eqnarray*}
E(y_i|z_i=1,\theta^{'}) &=& \int_t^{\infty}yf(y|y>t)dy \\
&=& \int_t^{\infty}yf(y-t)dy \\
&=& t+\theta^{'}
\end{eqnarray*}