  We present a catalog of stellar properties for a large sample of 6676 evolved
stars with APOGEE spectroscopic parameters and \textit{Kepler} asteroseismic
data analyzed using five independent techniques. Our data includes evolutionary
state, surface gravity, mean density, mass, radius, age, and the spectroscopic
and asteroseismic measurements used to derive them. We employ a new empirical
approach for combining asteroseismic measurements from different methods,
calibrating the inferred stellar parameters, and estimating uncertainties. With
high statistical significance, we find that asteroseismic parameters inferred
from the different pipelines have systematic offsets that are not removed by
accounting for differences in their solar reference values. We include
theoretically motivated corrections to the large frequency spacing ($\Delta
\nu$) scaling relation, and we calibrate the zero point of the frequency of
maximum power ($\nu_{\rm max}$) relation to be consistent with masses and radii
for members of star clusters. For most targets, the parameters returned by
different pipelines are in much better agreement than would be expected from
the pipeline-predicted random errors, but 22\% of them had at least one method
not return a result and a much larger measurement dispersion. This supports the
usage of multiple analysis techniques for asteroseismic stellar population
studies. The measured dispersion in mass estimates for fundamental calibrators
is consistent with our error model, which yields median random and systematic
mass uncertainties for RGB stars of order 4\%. Median random and systematic
mass uncertainties are at the 9\% and 8\% level respectively for RC stars.
