Tournament Staking Q

[stevoL]

ok so need a bit of math help with this one...

im going to be staking a friend in several of the wcoop and ftops tourneys soon and i need to figure out the best staking deal for both of us

now, because its only a shortterm thing the standard deal of 50/50 with makeup isnt really the best here, basically because theres not much incentive for him in the later tourneys if he's already in the hole by alot because he wont be getting any$$ unless he final tbls it sorta thing, by the way correct me if im wrong with any of my thinking

so, I want to create a deal that just gives him a certain % of profits for each tourney, no strings attached...seen as the standard is 50% with makeup, the % we end up with will be below 50% right? how to we figure this %

i presume how often he gets ITM is going to affect this alot

here are his recent tourney stats

total played - 1233
cashes - 183

ITM - 14.8%
ROI - 69.4%

so using these stats lets see what we can come up with!

thanks

[AaronBrown]

Is the ROI based on total buy-ins or net? That is, if each buy-in was $100, did he return 69.4% on $100*1,233, meaning his gross profit was $85,570? Or do you mean he started with, say, $2,000, and now has $2,000 + 0.694*$2,000 = $3,388? It makes a big difference to your deal.

Call the total buy-in you stake him to X. That's the total entry fees of all the tournaments and rebuys. Call his total winnings Y. You hope, of course, that Y > X.

Under the standard deal, if Y < X, you get Y and he gets nothing. If Y > X, you get (Y + X)/2 and he gets (Y - X)/2.

Instead, you propose to give him a*Y for some a, and you get all the rest. For this to be the same as the standard deal, you need:

a*Y = (Y - X)/2, so
a = (1 - X/Y)/2

Of course, you don't know Y, so you have to set a based on an expectation. If you think his gross ROI is 69.4%, you think X/Y = X/1.694*X = 1/1.694 = 0.590. That makes a (1 - 0.590)/2 = 0.410/2 = 0.205, or he gets about 20% of winnings.

If you expected him to do better, he should get a bigger share of the winnings. If you expect him to do worse, he should get a smaller share. That makes sense.

[stevoL]

69% roi means he's profitng $69 for every $100 in tourney fees...gets back $169 in a $100 tourney on average say

ok so all that math goes way over my head...20% does sound about right...ok so assuming 20%, whats MY expected roi% by staking him now?