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I think something a lot of people miss about the “short-term chartist position” (these trends have continued until time t, so I should expect it to continue to time t+1) for an exponential that’s actually a sigmoid is that if you keep holding it, you’ll eventually be wrong exactly once.
Whereas if someone is “short-term chartist hater” (these trends always break, so I predict it’s going to break at time t+1) for an exponential that’s actually a sigmoid is that if you keep holding it, you’ll eventually be correct exactly once.
Now of course most chartists (myself included) want to be able to make stronger claims than just t+1, and people in general would love to know more about the world than just these trends. And if you're really good at analysis and wise and careful and lucky you might be able to time the kink in the sigmoid and successfully be wrong 0 times, which is for sure a huge improvement over being wrong once! But this is very hard.
And people who ignore trends as a baseline are missing an important piece of information, and people who completely reject these trends are essentially insane.
Predicting an exponential or a sigmoid in perpetuity seems to be assuming there will not be another breakthrough. Breakthroughs don't have to replace transformers, they can add to them. It seems like that would change the shape of the curve.
Continual learning in various forms is the breakthrough I'm particularly thinking of here, but there are other possibilities.
2Jonas Hallgren
I've got a question which might be a bit galaxy brained which goes something like: If you start looking for a straight line on a graph aren't you gonna delude yourself because you're a stupid monkey?
Doubling down on this, if you join the straight line group then all the other people around you will show you the evidence of the straight line and start to dismiss the evidence of the sigmoiding?
I've got some sort of alarms firing in my head going like "the local environment seems like it leads to bad epistemics, care, care!" and so I've adapted the very elusive (and in reality non-existent) centrist position of saying "if it happens it happens, the stuff I work on is robust to timelines" and then actually having a model in the background but not being public about it. (which includes straight line arguments)
So uhhh, I'm taking all evidence into account and it may or may not be true in a very hypothetical world...
It's probably helpful to actually look at evidence and not solely rely on your prior, yes.
Part of the point of my comment is to suggest that "trend continues with some high probability", and the "trend breaks tomorrow" should be the exception, rather than ""trend breaks tomorrow" should be the default outcome, with "trend continues tomorrow" being the unlikely edge case.
But I agree there are adverse selection effects. If you go around looking for "interesting" straight lines on graphs you are disproportionately likely to trick yourself by bad data and/or the one trend that's more likely to break (because they're selected to be interesting).