A correlation and probability analysis of the distribution of arrival directions for a sample of AGASA events reported to have energies above 4 × 10 19 eV shows the small scale clustering to remain significant at the 99.5 − 99.9% CL and to be consistent with previous results. For the sample taken as a whole, there are no departures from either homogeneity or isotropy on angular scales greater than 5 degrees. The sample of events with E ≥ 6 × 10 19 eV contains no pairs with separations < 4 degrees. Cross correlating subsamples partitioned by energy reveals three uncorrelated distributions in the intervals 4− 5× 10 19 eV, 5− 8× 10 19 eV, and greater than 8× 10 19 eV. The partition with 5 ≤ E < 8×10 19 eV is correlated with the supergalactic equatorial plane while the other two groups are statistically consistent with isotropic distributions. The presence of three distinct energy-partitioned groups of events could reflect possible changes in primary composition, different source distributions, differing levels of GZK losses, or deflection effects of magnetic fields. PACS number(s): 95.85.Ry, 98.70.Sa Accepted for publication in Phys. Rev. D *

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