  We present the detailed analysis of Hubble Space Telescope observations of
the spatial distributions of different stellar species in two young compact
star clusters in the Large Magellanic Cloud, NGC 1805 and NGC 1818. Based on a
comparison of the characteristic relaxation times in their cores and at their
half-mass radii with the observed degree of mass segregation, it is most likely
that significant primordial mass segregation was present in both clusters,
particularly in NGC 1805. Both clusters were likely formed with very similar
initial mass functions.
