[SumZero]

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If you are better than average player in the field, you can find EV+ situations to use them, either to bully smaller stacks or to double up against a poor player with a stack larger than the buy in, this should outweigh your ability to avoid gambler's ruin by rebuying, but depends again on your skill versus the field

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But it depends on the field size, payout structure, if the field rebuys, and how much better you are (I.e., better than average isn't always good enough. Better than the rake also isn't always good enough). Let's imagine a case where you are playing a 10 person tournament where everybody buys-in for $1000+$100 and gets 1000 chips (and let's say everyone has the option of doing a $1000/T1000 rebuy). Let's further say that the rest of the field is equally good, while you have a 25% advantage over them. That is your skill with 100 chips is equal to their skill with 125 chips, etc. So at the start of the tournament it is like they all have 1000 chips and you have 1250 chips.

Let us say that it is a standard 50%, 30%, 20% payout. At the start of the tournament, using ICM with your +25% advantage:

If no one rebuys: You have an EV of $95.84 for an ROI of 8.7%.

If everyone, including you, rebuys: You have an EV of $291.68 for an ROI of 13.9%.

If everyone but you rebuys: You have an EV of $173.25 for an ROI of 15.8%.

If only you rebuys: You have an EV of $55.77 for an ROI of 2.7%.

If half the field (5 other players) rebuys and you do to: You have an EV of $233.02 for an ROI of 11.1%.

If half the field (5 other players) rebuys and you do not: You have an EV of $161.22 for an ROI of 14.7%.

So overall you actually do best (I.e., best ROI) in this situation, where you were a whole 25% better than the field per chip which was good enough for an 8.7% ROI after rake if this was a freeze out, when you do not make the mistake of rebuying and as many of your opponents do make this mistake. If you are willing to sacrifice ROI for EV (in other words seek greater risk of ruin for greater rewards at a worse return on investment) then everybody rebuying is the best situation (which makes sense since this makes it like a twice as expensive tournament with half the rake). But if none of your opponents are rebuying you make a serious error in both EV and ROI if you are the only one to rebuy.