<p>I think the largest factor (among several) is their greater financial wherewithal, but that's neither here nor there. Their throwing out large numbers of applications post-ED-rejection, increases their odds that they will be accepted at at least one, provided they are in the group of "qualified" applicants. Again, with a cross-Ivy admit rate in the 40-50% range, it's just not that hard, provided you are "qualified", and aren't picky about which one. There are state universities with lower admit rates. And forget the triumvirate of Caltech, MIT, and Cooper Union - now THAT'S tough.</p>