Talk:Mutilated chessboard problem/GA1

GA Review

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Reviewer: Ovinus (talk · contribs) 18:21, 14 September 2022 (UTC)[reply]

Shall review over the next few days.

GA review (see here for what the criteria are, and here for what they are not)

It is reasonably well written.
a (prose, spelling, and grammar): b (MoS for lead, layout, word choice, fiction, and lists):
It is factually accurate and verifiable.
a (reference section): b (citations to reliable sources): c (OR): d (copyvio and plagiarism):
All sources appear to be reliable. Suggest you mark [11] as open access or simply link the title. Earwig yields only reverse copies.
You mean Bilalić et al, now [12]? Ok, done, but in general I prefer to let the bots that run around adding doi-access tags handle this. Because of the subscription accesses that I have, it's not always obvious to me whether I can see a source because it's open or because I have a subscription. And I don't think the doi-access tag is especially helpful to readers; if they want to find a source, and an obviously-open source is not already linked from the url, then the next most obvious thing to do is click on the link regardless of whether it's open or not, and see what happens. The only thing the doi-access tag will do is, if you pay attention to it, give you some premonition that, when you do the thing you were going to do anyway regardless of what it said, you might not get to what you want. But that's true of all web links; they could have gone dead, or whatever other problem. —David Eppstein (talk) 19:42, 14 September 2022 (UTC)[reply]
It is broad in its coverage.
a (major aspects): b (focused):
It follows the neutral point of view policy.
Fair representation without bias:
It is stable.
No edit wars, etc.:
It is illustrated by images and other media, where possible and appropriate.
a (images are tagged and non-free content have non-free use rationales): b (appropriate use with suitable captions):
I vectorized the lead image. Any extra images would probably be excessive, and there's already one with a real chessboard. Ovinus (talk) 18:42, 14 September 2022 (UTC)[reply]
Overall:
Pass/Fail:

Spotchecks

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Content

The link of impossible puzzle puzzles me as it's about a specific, unrelated puzzle. Ovinus (talk) 22:21, 14 September 2022 (UTC)[reply]
Fixed by retargeting impossible puzzle to List of impossible puzzles, I think a more appropriate link target. The specific puzzle capitalizes the phrase differently (and is not impossible). —David Eppstein (talk) 22:41, 14 September 2022 (UTC)[reply]
"More generally, dominoes can cover all but two squares of the chessboard, if and only if the two uncovered squares are of different colors." How about recast to "More generally, if two squares are removed from a chessboard, ... two removed squares ..." Simpler parallelism Ovinus (talk) 22:21, 14 September 2022 (UTC)[reply]
Any reason why only Gamow & Stern is done inline with {{harvtxt}} in History and not the others? Ovinus (talk) 22:21, 14 September 2022 (UTC)[reply]
Not really, fixed. —David Eppstein (talk) 22:42, 14 September 2022 (UTC)[reply]
"It has been examined in studies of the nature of mathematical proof" I would suggest expansion of this point, as it's very interesting. For example, in the fourth one, about the difficulties of formalizing the question and its classic solution into a combinatorial statement Ovinus (talk) 22:21, 14 September 2022 (UTC)[reply]
Er. The reason I haven't expanded it in more detail is because my impression on trying to read this material is that it's bullshit. Or maybe more charitably, the point they were trying to make did not come across clearly enough for to me to be able to provide a useful summary of it. There are no actual difficulties in formalizing the classical solution, as the final sentence of "Application to automated reasoning" on automated proof assistants should make clear. —David Eppstein (talk) 22:45, 14 September 2022 (UTC)[reply]
Legendary. Then why cite it at all? And what about the other three refs Ovinus (talk) 23:03, 14 September 2022 (UTC)[reply]
It is obviously reliably published, on the philosophy of mathematics related to this problem, and I don't trust my judgement of it being bogus well enough to deliberately snub it. MacKenzie also states that the coloring argument "would not become a formal proof, in the sense in which this term is used in this paper, even if the everyday terms used in the puzzle were replaced by more precise mathematical equivalents", from which I can only conclude that I have no idea what he means by a formal proof, because to me the proof-assistant proofs are very much formal proofs in exactly the sense he describes: finite sequences of formulae each one of which follows from the previous by formal logical rules of inference, rather than merely arguments designed to convince other mathematicians of the truth of something. Kerber is less problematic, basically saying that a good proof should teach you something more than merely the truth of what it proves, that automated theorem provers should be flexible enough to handle higher-level proofs that provide useful intuition about the problem, and that some of the existing automated proofs actually do so. —David Eppstein (talk) 23:42, 14 September 2022 (UTC)[reply]
"If the two black corners are removed instead, then 32 white squares and 30 black squares remain, so it is again impossible" It may be obvious, but I'd suggest you mention that the colors may be interchanged, as it shows another way of looking at the problem. Ovinus (talk) 22:21, 14 September 2022 (UTC)[reply]
For Winograd's proof, it's probably wise to mention the trivial base case of 7 empty squares Ovinus (talk) 22:21, 14 September 2022 (UTC)[reply]