FLUCTUATIONS IN THE IRAS-1.2-JY CATALOG

An analysis of the IRAS 1.2 Jy redshift catalogue with emphasis on the separate examination of northern and southern parts (in galactic coor dinates) is performed using a complete set of morphological descriptor s (Minkowski functionals), nearest neighbour distributions and the var iance of the galaxy counts. We find large fluctuations in the clusteri ng properties as seen in a large difference between the northern and s outhern parts of the catalogue on scales of 100h(-1)Mpc. These fluctua tions remain discernible even on the scale of 200h(-1)Mpc. We also ide ntify sparse sampling as a major source of ''apparent homogenization'' . Tests on observational selection effects concerning luminosity, colo ur and redshift-space distortion support the significance of these lar ge-scale fluctuations.