Retransformation bias
= Retransformation bias
In general, $\mathbb E[Y\mid X]$ is not obtained by exponentiating $\mathbb E[\log Y\mid X]$. For log-normal errors of variance $\sigma^2$, the correction factor is $e^{\sigma^2/2}$.
= Retransformation bias
In general, $\mathbb E[Y\mid X]$ is not obtained by exponentiating $\mathbb E[\log Y\mid X]$. For log-normal errors of variance $\sigma^2$, the correction factor is $e^{\sigma^2/2}$.