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I am currently studying for the CS251 Cryptocurrencies and Blockchain Technologies exam. In a past exam, there is this question without an answer and I would really appreciate your help so that I can better understand it:

Recall that a selfish miner temporarily refrains from publishing mined blocks in an effort to get several blocks ahead of other miners, thereby causing other miners to waste effort mining orphan blocks. When a selfish miner is only one block S ahead of the public chain, if another miner mines and publishes a block O at the same height as S, the selfish miner immediately publishes S. Let γ be the probability that, when this happens, an honest miner will try to mine the next block on S instead of on O.

A) How can an attacker ensure that γ ≈ 1 (in other words, S almost always overrides O) on today’s Bitcoin network?

Thank you very much in advance for your help!

Python-Data-Science-Learner
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    A guess: what if the selfish miner deliberately omits from S a number of high-fee transactions that are in O? Then other miners have an incentive to mine on S, because then they can claim the fees of those transactions, whereas with O they could not. – Nate Eldredge Jul 29 '21 at 16:45
  • @NateEldredge That's a good one! I would not have thought of that. – bigjosh Jul 29 '21 at 19:44
  • @NateEldredge thanks! So you mean the selfish miner omits the high transaction fee transactions so that miners have the chance to get a block with them for the next block? – Python-Data-Science-Learner Jul 30 '21 at 08:49
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    @Python-Data-Science-Learner: Right. But I don't know if that's what your exam has in mind. I also don't know whether your exam would consider a miner "honest" who would mine on S instead of O to get more fees, despite having seen O first. – Nate Eldredge Jul 30 '21 at 12:21

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