Risk of Ruin over 7 events

[New2This]

Hello!

A friend will be staking me for several smaller WSOP events, specifically three $1,500 events, two $2,000 events and two $1,000 rebuy events.

I'm trying to help him determine his Risk of Ruin (how likely he is to make exactly $0) over this very small sample. We both understand that the accuracy of this figure will be quite low considering the absurd sample size, but we want to figure it out anyway.

Online my average buyin is ~$70, i regularly place very high in the $75FTP and the $22rebuy on PStars. My online ROI is roughly 80% over 2000+ tournaments, my live ROI is ~350% over 50 games including 4 final tables with significant ($5k+) cashes.

I don't know my ROI in these very large, slow events. I expect i'll be one of the best players in each of the events i play in, perhaps with the exception of the $1k rebuys.

Sooooo, how do i calculate my RoR over this small sample? My friend understands that my average result and the expected actual result will be quite different. I'd presume i'll make it to the $$$ in 2-3 events with a decent shot of getting 1 Final Table over the course of 7 events.

Any ideas?