<p>For ED, it does have some advantage if your credential is at or above admission average mainly because of the binding commitment. Also, there are less applicants for ED as there is a limit of one per student. For the RD, there is no limit for application and there are much much more applications (including those rejected or deferred from other ED) competing for the remaining spots. The chance is obviously lower. But if your credential is below admission average, there is little reason why a prestigious would accept less qualify students early as they know there will be more high quantity applicants coming for RD.</p>