  Jets produced in high energy heavy ion collisions are quenched by the quark
gluon plasma. Measurements of these jets are influenced by the methods used to
suppress and subtract the large, fluctuating background and the assumptions
inherent in these methods. We compare the measurements of the background in
Pb+Pb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV by the ALICE Collaboration
$\underline{(B. Abelev \textit{et al.}, J. High Energy Phys. \mathbf{2012},
053)}$ to calculations in TennGen (a data-driven random background generator)
and PYTHIA Angantyr. A detailed understanding of the width of these
fluctuations is important for reducing uncertainties due to unfolding and
extending measurements to lower momenta and larger resolution parameters. The
standard deviation of the energy in random cones in TennGen is approximately in
agreement with the form predicted in the ALICE paper, with deviations of 1--6%.
The standard deviation of energy in random cones in Angantyr exceeds the same
predictions by approximately 13%. Deviations in both models can be explained by
the assumption that the single-particle $d^2N/dy$ $dp_T$ is a gamma
distribution in the derivation of the prediction, whereas the model uses a
different distribution. This indicates that model comparisons are potentially
sensitive to the treatment of the background. We demonstrate that unfolding
methods used to remove background fluctuations from jets can affect the
comparisons between models and data, $\textit{even in the absence of detector
effects}$. Our findings suggest the need to more carefully consider methods for
comparing simulations and data.
