  (Abridged) We have conducted a study of [NeII] line emission based on a
sample of 92 pre-main sequence stars mostly belonging to the infrared Class II,
including 13 accreting transition disk objects and 14 objects driving jets and
outflows. We find several significant correlations between L[NeII] and stellar
parameters, in particular LX and the wind mass loss rate, dM/dt. Most
correlations are, however, strongly dominated by systematic scatter. While
there is a positive correlation between L[NeII] and LX, the stellar mass
accretion rate, dMacc/dt, induces a correlation only if we combine the largely
different subsets of jet sources and stars without jets. Our results suggest
that L[NeII] is bi-modally distributed, with separate distributions for the two
subsamples. The jet sources show systematically higher L[NeII], by 1-2 orders
of magnitude with respect to objects without jets. Jet-driving stars also tend
to show higher mass accretion rates. We therefore hypothesize that the trend
with dMacc/dt reflects a trend with dM/dt that is more physically relevant for
[NeII] emission. L[NeII] measured for objects without known outflows and jets
is found to agree with simplified calculations of [NeII] emission from disk
surface layers if the measured stellar X-rays are responsible for heating and
ionizing of the gas. The large scatter in L[NeII] may be introduced by
variations of disk properties and the irradiation spectrum, as previously
suggested. The systematically enhanced [NeII] flux from jet sources clearly
suggests a role for the jets themselves, as previously demonstrated by a
spatially resolved observation of the outflow system in the T Tau triple.
