  We describe two different approaches for incorporating systematics into
analyses for parameter determination in the physical sciences. We refer to
these as the Pragmatic and the Full methods, with the latter coming in two
variants: Full Likelihood and Fully Bayesian. By the use of a simple and
readily understood example, we point out the advantage of using the Full
Likelihood and Fully Bayesian approaches; a more realistic example from
Astrophysics is also presented. This could be relevant for data analyses in a
wide range of scientific fields, for situations where systematic effects need
to be incorporated in the analysis procedure. This note is an extension of part
of the talk by van Dyk at the PHYSTAT-Systematics meeting.
