RDP 2018-08: Econometric Perspectives on Economic Measurement Equation (13)

\begin{array}{l} E [{\hat{α}}_{j} - {\hat{α}}_{i}] = α_{j} - α_{i} ⇏ & E [e^{{\hat{α}}_{j} - {\hat{α}}_{i}}] = \end{array} e^{α_{j} - α_{i}}