Figure 3 - PDF and confidence ellipsoid projections

The non-linear Grid-search produces a 3D, xyz joint PDF (red) which represents the integral of the full, 4-D PDF over origin time. The 3D, xyz confidence ellipsoid produced by Hypoellipse (green ellipse) represents the integral over origin time of a 4-D, ellipsoidal estimate (green ellipsoid) of the full, 4-D PDF.