In what became 5th most-read new post on LessWrong in 2012, Morendil told us about a study widely cited in its field... except that source cited, which isn't online and is really difficult to get, makes a different claim — and turns out to not even be the original research, but a PowerPoint presentation given ten years after the original study was published!
Fortunately, the original study turns out to be freely available online, for all to read; Morendil's post has a link. The post also tells us the author and the year of publication. But that's all: Morendil didn't provide a list of references; he showed how the presentation is usually cited, but didn't give a full citation for the original study.
The link is broken now. The Wayback machine doesn't have a copy. The address doesn't give hints about the study's title. I haven't been able to find anything on Google Scholar with author, year, and likely keywords.
I rest my case.
One could also appeal to the story about Gauss as a child adding up 1..100 by a clever trick, and none of his classmates figuring it out despite clearly seeing that Gauss must've done something clever.
But notice how your example does not fit my points: "since you don't know how they solved it or usually how long they took"; in this case, you have a very good estimate of how long it will take them to use the O(n) summation algorithm from all your past sums, and since you were all assigned the problem at the same time, you also know precisely how long it took them.
In the Shannon anecdote, you know nothing about how long it took the brother to answer it nor, given how heterogenous puzzles can be, how long it might take him to solve it, nor is there even any 'brute force' approach for most puzzles which you could compare against a 'clever' approach and so choose to look for a clever approach rather than spend more time executing the brute force approach.
Similarly for web searching, there's typically no brute force approach at all: if Google spits out a list of 10 hits total for the paper title and you look at all 10 and they fail, then what? What's the dumb brute force approach in searching? You simply have to try another 'clever' approach, because you've exhausted all your available data.
Sorry, you're right, I didn't read your previous post carefully enough.
I agree that if this phenomenon is real, in order to explain it in terms of a rational agent you do need to either know something about the person who solved it, or how long they took, or some other detail about them in order for this to be helpful in any way.
In the real world, however, a declaration of having solved the problem always leaves some sort of knowledge. In the web search case that just unfolded in this thread, by posting a solution you leaked the information that a solutio... (read more)