Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A COMPARATIVE STUDY OF MORPHOLOGICAL CLASSIFICATIONS OF APM GALAXIES   We investigate the consistency of visual morphological classifications of
galaxies by comparing classifications for 831 galaxies from six independent
observers. The galaxies were classified on laser print copy images or on
computer screen produced from scans with the Automated Plate Measuring (APM)
machine. Classifications are compared using the Revised Hubble numerical type
index T. We find that individual observers agree with one another with rms
combined dispersions of between 1.3 and 2.3 type units, typically about 1.8
units. The dispersions tend to decrease slightly with increasing angular
diameter and, in some cases, with increasing axial ratio $(b/a)$. The agreement
between independent observers is reasonably good but the scatter is
non-negligible. In spite of the scatter the Revised Hubble T system can be used
to train an automated galaxy classifier, e.g. an Artificial Neural Network, to
handle the large number of galaxy images that are being compiled in the APM and
other surveys.

2
The categories of this paper are: math
31
The categories of this paper are: ao-sci
22
The categories of this paper are: chao-dyn
16
The categories of this paper are: stat
14
The categories of this paper are: math-ph
1
The categories of this paper are: cs
27
The categories of this paper are: comp-gas
0
The categories of this paper are: hep-ph
32
The categories of this paper are: atom-ph
21
The categories of this paper are: adap-org
26
The categories of this paper are: bayes-an
35
The categories of this paper are: mtrl-th
20
The categories of this paper are: acc-phys
30
The categories of this paper are: q-alg
12
The categories of this paper are: nucl-th
36
The categories of this paper are: cmp-lg