  We study the magnetization-switching statistics following reversal of the
applied field for three separate computational models representing the same
physical system, an iron nanopillar. The primary difference between the models
is the resolution of the computational lattice and, consequently, the intrinsic
parameters that must be rescaled to retain similarity to the physical system.
Considering the first-passage time to zero for the magnetization component in
the longitudinal (easy-axis) direction, we look for applied fields that result
in bimodal distributions of this time for each system and compare the results
to the experimental system. We observe that the relevant fluctuations leading
to bimodal distributions are different for each lattice resolution and result
in magnetization-switching behavior that is unique to each computational model.
Correct model resolution is thus essential for obtaining reliable numerical
results for the system dynamics.
