  Principal Component Analysis (PCA) is a well-known technique used to
decorrelate a set of vectors. It has been applied to explore the star formation
history of galaxies or to determine distances of mass-lossing stars. Here we
apply PCA to the optical data of Planetary Nebulae (PNe) with the aim of
extracting information about their morphological differences. Preliminary
analysis of a sample of 55 PNe with known abundances and morphology shows that
the second component (PC2), which results from a relation produced by the
parameters log(N/O), initial and final mass of PNe, is depending on the
morphology of PNe. It has been found that when log(N/O) < -0.18 the PNe's
nitrogen is low independently on the oxygen abundance for either Bipolar (B),
Elliptical (E) or Round (R) PNe. An interesting result is that both E and R PNe
have log(N/O) < 0 while only B PNe show negative and positive values.
Consequently, B PNe are expected to have higher nitrogen values than the E and
R PNe. Following that and a second sample of 35 PNe, n_{e} is also found to be
higher in B PNe. Also, in all PNe morphologies PC2 appears to have a minimum at
0.89 and PNe's initial mass at 2.6 solar masses. 5-D diagrams between PCAs
components and physical parameters are also presented. More results will follow
while simple models will be applied in order to try to give a physical meaning
to the components.
