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J. R. Kriessler, E. H. Han (U. Minnesota), S. C. Odewahn (Caltech), T. C. Beers (Michigan State U.)
We present preliminary results of a study to evaluate which is the more fundamental relationship in galaxy morphology within galaxy clusters -- the local density of the galaxy environment or the projected distance of the galaxy from the cluster center. The completed sample will contain 107 Abell clusters, including all northern Abell clusters with distance class \le 4 and richness class \ge 1 with galactic latitude \vert b \vert > 30. Morphological information for the galaxies is obtained by application of an automated image classification technique to the APS scans of the POSS I. The galaxy classification procedure, which uses a decision-tree code, will be discussed in detail. Currently, we have achieved an accuracy of 85% (10-fold cross validation error as judged from a sample of 1500 galaxies classified visually) within the broad classes of Early (E,S0), Intermediate (Sa,Sb,Sc), and Late (Sd,Im) galaxy types using a variety of derived photometric parameters. Efforts to improve the resolution of the classifier using a wavelet based image analysis scheme to quantify the amount of structure in each galaxy image will also be discussed.