Distance determination for RAVE stars using stellar models III: The
  nature of the RAVE survey and Milky Way chemistry
  We apply the method of Burnett & Binney (2010) for the determination of
stellar distances and parameters to the internal catalogue of the Radial
Velocity Experiment (Steinmetz et al. 2006). Subsamples of stars that either
have Hipparcos parallaxes or belong to well-studied clusters, inspire
confidence in the formal errors. Distances to dwarfs cooler than ~6000 K appear
to be unbiased, but those to hotter dwarfs tend to be too small by ~10% of the
formal errors. Distances to giants tend to be too large by about the same
amount. The median distance error in the whole sample of 216,000 stars is 28%
and the error distribution is similar for both giants and dwarfs. Roughly half
the stars in the RAVE survey are giants. The giant fraction is largest at low
latitudes and in directions towards the Galactic Centre. Near the plane the
metallicity distribution is remarkably narrow and centred on [M/H]-0.04 dex;
with increasing |z| it broadens out and its median moves to [M/H] ~ -0.5. Mean
age as a function of distance from the Galactic centre and distance |z| from
the Galactic plane shows the anticipated increase in mean age with |z|.
