Inference from modelling the chemodynamical evolution of the Milky Way
  disc
  In this thesis, the field star Initial Mass Function (IMF) and chemical
evolution parameters for the Milky Way (MW) are derived using a forward
modelling technique in combination with Bayesian statistics. Starting from a
local MM disc model, observations of stellar samples in the Solar Neighbourhood
are synthesised and compared to the corresponding volume-complete observational
samples of Hipparcos stars. The resulting IMF, derived from observations in the
range from 0.5 to 8Msun, is a two-slope broken power law with powers of -1.49
+- 0.08 and -3.02 +- 0.06 for the low-mass slope and the high-mass slope,
respectively, with a break at 1.39 +- 0.05Msun. In order to constrain the IMF
for stars more massive than 8Msun, a fast and flexible chemical enrichment
code, Chempy, was developed, which is also able to reproduce spatial and
stellar population selections of observational samples. The inferred high-mass
slope for stellar masses above 6Msun is -2.28 +- 0.09, accounting for the
systematic effects of different yield sets from the literature. This shows that
constraints from chemical modelling, similarly to hydrodynamical simulations of
the Galaxy, demand a Salpeter high-mass index. This is hard to recover from
star count analysis given the rareness of high-mass stars.
