  The origin of high-energy (HE) astrophysical neutrinos has remained an
elusive hot topic in the field of HE astrophysics for the past decade. Apart
from a handful of individual associations, the vast majority of HE neutrinos
arise from unknown sources. While there are theoretically-motivated candidate
populations, such as blazars -- a subclass of AGN with jets pointed towards our
line-of-sight -- they have not yet been convincingly linked to HE neutrino
production. Here, we perform a spatio-temporal association analysis between a
sample of blazars (from CGRaBS catalog) in the radio and optical bands and the
most up-to-date IceCube HE neutrino catalog. We find that if the IceCube error
regions are enlarged by 1$^\circ$ in quadrature, to account for unknown
systematic errors at maximal level, a spatio-temporal correlation between the
multiwavelength light curves of the CGRaBS blazars and the IceCube HE neutrinos
is hinted at least at a 2.17$\sigma$ significance level. On the other hand,
when the IceCube error regions are taken as their published values, we do not
find any significant correlations. A discrepancy in the blazar-neutrino
correlation strengths, when using such minimal and enlarged error region
scenarios, was also obtained in a recent study by the IceCube collaboration. In
our study, this difference arises because several flaring blazars -- coinciding
with a neutrino arrival time -- happen to narrowly miss the published
90\%-likelihood error region of the nearest neutrino event. For all of the
associations driving our most significant correlations, the flaring blazar is
much less than 1$^\circ$ away from the published error regions. Therefore, our
results indicate that the question of the blazar-neutrino connection is highly
sensitive to the reconstruction of the neutrino error regions, whose
reliability is expected to improve with the next generation of neutrino
observatories.
