Assuming as many people will start at Wharton in fall 2011 as did last year (817) and that 90% of the class is already full. Now if Wharton hasn’t accepted any extra candidates, admits so far stand at 735 (817*0.9). The historical yield figure at Wharton is around 70%, which means 221(0.3*735) people will decline the offer.
Assuming the volume of applications received in round 3 is consistent with that of other rounds. For Wharton to find 10% of the class, 10% of the total applicants will apply in round 3, which will be 10% of 6819, or 682. And Wharton will interview 273 (40% of 682) applicants in round 3.
Therefore, total number of open spots = 817*1.43 (for 70% yield)*0.1+ 221 = 117 + 221 = 338
Total candidates waiting for a decision after round 3 interviews = 273 + people on the waitlist (221?)
Chances of getting in = 338/ 494 = 68%
But I don’t think Wharton hasn’t accepted any extra candidates. On the other extreme, for Wharton to completely account for the yield, it must accept 43% more candidates (1.43*0.7= 1).
If nothing is going to come out of the yield adjustment, which appears to be the likely case, the chances of getting in stand at (117/494) 24%
The gist of the analysis is that there are around 117 open spots and the success rate largely depends on how many candidates apply in round 3.
By the way, I’m a round 2 waitlister too.