Originally Posted by Dorkus Malorkus
If you do rebuy, you pay $10 extra. As you have an ROI of 50%, you can expect, in the long run, that this further investment of $10 will actually be worth $15 ($10+($10*0.5)). In actuality, it may be worth a little less than this due to you having a short stack, but you can still expect a positive return as long as you have a reasonable ROI. Thus whenever you elect not to rebuy, you are losing $5 in value.
There's a flaw in the first part of this argument as you half point out. You assume the ROI on a rebuy to give you half the stack of everyone else is the same as your normal tournament ROI, whereas I'm pretty sure it would be a lot lower.
I can see the arguments for doing an "instant" rebuy to double your chips at the beginning, because you're at a disadvantage if you don't.
But I don't agree that you should ever rebuy after being busted out in an online tournament. Simply because, as you say, your ROI on this rebuy will be less because you're now the short stack, and you're re-starting at a disadvantage to everyone else. You can get a better return on this money by simply going and entering another tournament where you're on a level playing field again.
Not trying to be argumentative, but is there any flaw in this logic? Can anyone claim that the ROI on a rebuy for a small stack in the middle of a tourney is higher than your normal tournament ROI? If not, there's no reason to rebuy.
The only reasons I can think of that would rebuy are
a) You're enjoying the company and it's a fun table
b) It's a live tournament and you've spent a whole lot of time and effort travelling to the venue, and there isn't another tournament you can enter