The payoff and optimal move naturally depends on the exact time of measurement. Before receiving any letter you can save $1000 by precomitting to not paying: but that is a move both FDT and EDT will make. But after receiving the letter (which you assumed) the optimal move is to pay the $1000 to save $1M. FDT from my understanding fails here as it retroactively precommits to not paying and thus loses $1M. So this is a good example of where EDT > FDT.
The only example i’ve seen so far where the retroactive precommitment of FDT actually could make sense is the specific variant 5 from here where we measure utility before the agent knows the rules or has observed anything. And even in that scenario FDT only has a net advantage if it is optimal to make the universal precommitmment everywhere. EDT can decide to do that: EDT->FDT is allowed, but FDT can never switch back. So in that sense EDT is ‘dominant’, or the question reduces to: is the universal precommitment of FDT a win on net across the multiverse? Which is far from clear.
The payoff and optimal move naturally depends on the exact time of measurement. Before receiving any letter you can save $1000 by precomitting to not paying: but that is a move both FDT and EDT will make. But after receiving the letter (which you assumed) the optimal move is to pay the $1000 to save $1M. FDT from my understanding fails here as it retroactively precommits to not paying and thus loses $1M. So this is a good example of where EDT > FDT.
The only example i’ve seen so far where the retroactive precommitment of FDT actually could make sense is the specific variant 5 from here where we measure utility before the agent knows the rules or has observed anything. And even in that scenario FDT only has a net advantage if it is optimal to make the universal precommitmment everywhere. EDT can decide to do that: EDT->FDT is allowed, but FDT can never switch back. So in that sense EDT is ‘dominant’, or the question reduces to: is the universal precommitment of FDT a win on net across the multiverse? Which is far from clear.