I didn’t read http://www.probabilityandfinance.com/ but I heard (maybe Vanessa Kosoy was saying this?) that it has a lot of ideas that people around here would attribute to logical induction.

While I’m here, I’ll echo several other commenters in pushing back against the insinuation that reinventing ideas is a sign of something going wrong. There are only so many hours in a day, and they trade off between

• (A) “try to understand the work / ideas of previous thinkers” and
• (B) “just sit down and try to figure out the right answer”.

It’s nuts to assert that the “correct” tradeoff is to do (A) until there is absolutely no (A) left to possibly do, and only then do you earn the right to start in on (B). People should do (A) and (B) in whatever ratio they expect to be most effective for figuring out the right answer. I often do (B), and I assume that I’m probably reinventing a wheel, but it’s not worth my time to go digging for it. And then maybe someone shares relevant prior work in the comments section. That’s awesome! Much appreciated! And nothing went wrong anywhere in this process! See also here.

If you dig through the SolidGoldMagikarp post, you can find earlier citations for this class of tokens, but sometimes people omit that earlier work when talking about the phenomenon.

Stephen Casper gives the example of "superposition" as a reinvented concept.

The way to reduce the rate of stuff like this is obviously more scholarship and humility. But I think most of the time, it's not a big deal, and only people doing active research or outreach should really worry about it. If a student calls it "superposition" and thinks it's a LW-sphere thing to work on, they're not doing any material harm.

Reinventing something and making it better is good.

Situating the Contributions of LessWrong to the Philosophy of Language by @Suspended Reason seems to address this topic in a pretty thorough fashion.

Confounders - This post took some vivid examples and turned them into solid recommendations, even referring to the concept that already exists outside the post. But it mints new laws where none are needed, not really addressing other things that contribute to the internal validity of experiments or the inferences from full programs of research that might counteract the call to measure every single thing you possibly can; in my estimation, it led to a minor weakness in the post. It's not an egregious reinvention because it has the intellectual humility to interact with previous scholarship, one cannot expect any individual post to cover all the pieces of what can be a broad domain, and the point seemed to be more of presenting preferred operating procedures rather than (re)introducing a concept.

Comparative advantage - and even worse, EY didn't even fully reinvent it. He just lined up a bundle of things that fall under the umbrella and called it a job well done. This particular instance also checks the boxes for arrogance and lack of rigor. That post was a fun read, but the embedded disdain for economics textbooks was particularly galling since economics textbooks handle the concept just fine.