  Among their competitors, projection depth and its induced estimators are very
favorable because they can enjoy very high breakdown point robustness without
having to pay the price of low efficiency, meanwhile providing a promising
center-outward ordering of multi-dimensional data. However, their further
applications have been severely hindered due to their computational challenge
in practice. In this paper, we derive a simple form of the projection depth
function, when (\mu, \sigma) = (Med, MAD). This simple form enables us to
extend the existing result of point-wise exact computation of projection depth
(PD) of Zuo and Lai (2011) to depth contours and median for bivariate data.
