User talk:David Eppstein

Hi, and welcome to my User Talk page! For new discussions, I prefer you add your comments at the very bottom and use a section heading (e.g., by using the "New section" tab at the top of this page). I will respond on this page unless specifically requested otherwise. For discussions concerning specific Wikipedia articles, please include a link to the article, and also a link to any specific edits you wish to discuss. (You can find links for edits by using the "compare selected revisions" button on the history tab for any article.)

Regarding Special:Diff/1267026607, "45th degree" is correct, but the paragraph was both terrible and also redundant with a slightly less bad passage earlier in the article. XOR'easter (talk) 22:47, 3 January 2025 (UTC) [reply ]

Thanks. Looks like "8°" was also correct, rather than "45°". —David Eppstein (talk) 00:05, 4 January 2025 (UTC) [reply ]

Hi, Professor David Eppstein. I want to create an article on Graham Priest's book An Introduction to Non-Classical Logic . The problem is that I am having a lot of trouble finding a lot of book reviews. I know you are very good at finding them. Please, could you help me on this? (the ones I've found I've already added to the page Graham Priest bibliography). Thank you. MathKeduor7 (talk) 03:53, 4 January 2025 (UTC) [reply ]

My usual searches of MathSciNet, zbMATH, JSTOR, and Google Scholar found: MR 1848144 & MR 2412933 (Boričić); JSTOR 20131881 (Shapiro Rev Metaphys); JSTOR 4617265/doi:10.1017/S1079898600002730 & JSTOR 25433856/doi:10.1017/S1079898600001505 (Hájek BSL); Zbl 0981.03002 & Zbl 1148.03002 (Mackenzie); Zbl 1152.03001 (Mullin review of German translation); doi:10.1080/00048400903097802 (Butchart Austral J Phil); doi:10.5840/teachphil201033453 (Yaqub Teach Phil); [1] (Leeb Hist Phil Log); [2] (Bonevac Phil in Rev)

In all cases I just searched for the title (ti:"Title" in MathSciNet/zbMath, intitle:"Title" in GS, advanced search for the quoted phrase + "reviews" checkbox in JSTOR). They also turned up Roy "Natural Derivations for Priest" which is not a review but looks relevant. The abbreviated metadata for the reviews is something I often do while compiling these lists to be able to match the duplicates to each other; in some cases, though, some of the ones that look like dups are instead re-reviews of the 2nd edition. Anyway, I think that should be plenty. —David Eppstein (talk) 06:48, 4 January 2025 (UTC) [reply ]

Thank you so much! MathKeduor7 (talk) 12:03, 4 January 2025 (UTC) [reply ]

P.S. It's funny, now there are so many sources (and of two different editions) that it's becoming difficult to write the article. It's like I went down the rabbit hole!, haha. Thanks again. P.P.S. I am lost, haha. MathKeduor7 (talk) 01:48, 5 January 2025 (UTC) [reply ]

I think I need to improve the structure of the article to have a chance of writing a decent article.! Maybe separating the references for the first edition from the references for the second edition. Something like that. Do you agree? Thanks. MathKeduor7 (talk) 23:55, 6 January 2025 (UTC) [reply ]

I usually try to have separate sections describing the material covered by a book (factual), and then discussing what audience it is aimed at and what else its critics thought about it (titled "audience and reception", more opinion-based, but with all opinions sourced to published reviews). —David Eppstein (talk) 00:00, 7 January 2025 (UTC) [reply ]

Thank you! I'll try this tomorrow (now I need to sleep!). MathKeduor7 (talk) 00:03, 7 January 2025 (UTC) [reply ]

Thank you again. I underestimated the difficulty of writing an article about a book. The result is that the article is a mess for now (but I am improving it!). MathKeduor7 (talk) 10:10, 7 January 2025 (UTC) [reply ]

Practice makes perfect. —David Eppstein (talk) 17:54, 7 January 2025 (UTC) [reply ]

Some of the best sources for Feynman's Lost Lecture are just never-published arXiv preprints (it seems the authors never cared much about publishing the papers), should I remove immediately or maybe send e-mails to the authors asking them to publish the papers so that they can be used on Wikipedia? Best regards! MathKeduor7 (talk) 02:19, 6 January 2025 (UTC) [reply ]

Hi User:David Eppstein Maybe I should have written more about Science-wide author databases of standardized citation indicators to justify its presence in the H-index page. This index is based on

• Total citations;
• Hirsch h-index;
• Coauthorship-adjusted Schreiber hm-index;
• The number of citations to papers as a single author;
• The number of citations to papers as single or first author;
• The number of citations to papers as single, first, or last author.

So I would say that it belongs to the H-Index page as it is an effort to improve on the measure H. For this reason I would now undo your deletion and say a bit more about it. I welcome your comments. All the best. Andrea Saltelli Saltean (talk) 10:52, 8 January 2025 (UTC) [reply ]

Hi, Professor. Sorry to take your time, but... Do you think Flávio Kapczinski is notable enough to have an article on Wikipedia? (I've already created it...) MathKeduor7 (talk) 18:07, 8 January 2025 (UTC) [reply ]

Membership in the Brazilian Academy of Sciences should be enough, yes. —David Eppstein (talk) 18:24, 8 January 2025 (UTC) [reply ]

Thank you! MathKeduor7 (talk) 18:33, 8 January 2025 (UTC) [reply ]

He does research with public money and hides his contact email. I managed to find it, with difficulty, because I have high Google Search skills, but since I suffer from bipolar disorder type 1 and I haven't slept for 4 days, things are getting difficult. I'm mad at him, can I say that he hides his contact email? (it's true) Or maybe it would be a violation of BLP? MathKeduor7 (talk) 02:28, 9 January 2025 (UTC) [reply ]

I should not have created an article about a guy who charges R$ 2.000 [3] for a single consultation. MathKeduor7 (talk) 02:33, 9 January 2025 (UTC) [reply ]

Why do you think he owes you his time and his contact info?? —David Eppstein (talk) 02:48, 9 January 2025 (UTC) [reply ]

He does his research with public money, from my taxes (high taxes in Brazil!), it is his duty to at least respond to an email. Also, his most important papers are all pay-walled (Elsevier etc). Not a good example, IMO. MathKeduor7 (talk) 04:15, 9 January 2025 (UTC) [reply ]

Being paid to do research and to teach are not the same as being paid to be available to the public. If Brazil uses taxes to pay airport security officers, does that give you the right to demand that they come to your house and provide security for you instead? —David Eppstein (talk) 05:33, 9 January 2025 (UTC) [reply ]

I see it now... I admit I'm wrong and you're right. Thank you for clarifying the issue. MathKeduor7 (talk) 05:43, 9 January 2025 (UTC) [reply ]

Hi!! Do you think it's ready? MathKeduor7 (talk) 08:36, 9 January 2025 (UTC) [reply ]

It'll probably appear in the main page! MathKeduor7 (talk) 07:00, 10 January 2025 (UTC) [reply ]

Hi, Professor. I think we can start with just one reference, then add what the second ref says, then the third's content, and so son. This way we get out of the rabbit hole. What do you think? MathKeduor7 (talk) 07:03, 10 January 2025 (UTC) [reply ]

Please, could you criticize Science and Sanity ? MathKeduor7 (talk) 07:03, 10 January 2025 (UTC) [reply ]

Btw, shouldn't it be in public domain already? MathKeduor7 (talk) 10:31, 10 January 2025 (UTC) [reply ]

Not if it was published in the US in 1933 and had its copyright renewed. The cutoff is 1930. In some other countries it is author's lifetime + 50 years, and under those systems it would be public domain. —David Eppstein (talk) 18:03, 10 January 2025 (UTC) [reply ]

I can't move Olympiad mathematics to Mathematical Olympiad. Dunno why. Please, could you make a technical move? (I did not understand how it works) MathKeduor7 (talk) 18:48, 10 January 2025 (UTC) [reply ]

Technically, I could, but I think in this case it needs a discussion and a consensus rather than a unilateral move. —David Eppstein (talk) 19:16, 10 January 2025 (UTC) [reply ]

Right! What is the procedure for opening the discussion? Thank you! MathKeduor7 (talk) 19:18, 10 January 2025 (UTC) [reply ]

Wikipedia:Requested moves —David Eppstein (talk) 19:23, 10 January 2025 (UTC) [reply ]

Thank you again! MathKeduor7 (talk) 19:24, 10 January 2025 (UTC) [reply ]

Done! MathKeduor7 (talk) 19:27, 10 January 2025 (UTC) [reply ]

I was under the effect of high doses of hypnotic medications when I created this article. I think she meets WP:GNG, but the sources are mostly in Spanish, making it hard to find and check them. MathKeduor7 (talk) 13:31, 12 January 2025 (UTC) [reply ]

Btw, if you want to laugh a bit: https://en.wikipedia.org/w/index.php?title=Talk:David_Eppstein&diff=prev&oldid=1268986383 hahaha MathKeduor7 (talk) 13:33, 12 January 2025 (UTC) [reply ]

I am in mania, I shouldn't be editing Wikipedia. Please, could you block me for two weeks? I'm serious, the psychiatrist told me to read a book quietly in my room... MathKeduor7 (talk) 13:49, 12 January 2025 (UTC) [reply ]

@331dot: Please? Only two weeks and I'll be better. MathKeduor7 (talk) 13:52, 12 January 2025 (UTC) [reply ]

I don't know many admins. But someone needs to block me for a while. Please. MathKeduor7 (talk) 13:54, 12 January 2025 (UTC) [reply ]

@Yamla: Please? MathKeduor7 (talk) 14:17, 12 January 2025 (UTC) [reply ]

Btw, I've just found Category:Wikipedia administrators willing to consider placing self-requested blocks! MathKeduor7 (talk) 15:16, 12 January 2025 (UTC) [reply ]

@Bishonen: Please, could you block me for two weeks? I am suffering from bipolar disorder issues. I am getting better, but I worry... MathKeduor7 (talk) 15:19, 12 January 2025 (UTC) [reply ]

To any admin reading this: I request my own block (for two weeks), because I am in mania. MathKeduor7 (talk) 15:24, 12 January 2025 (UTC) [reply ]

WP:BLOCKME, Please. MathKeduor7 (talk) 15:28, 12 January 2025 (UTC) [reply ]

I am crying, please someone block me. MathKeduor7 (talk) 15:33, 12 January 2025 (UTC) [reply ]

MathKeduor7, please tell me if you have read my block conditions here and if you accept them. Then I'll block you for two weeks. Tell me on my own page, not here on this random page. Bishonen | tålk 15:39, 12 January 2025 (UTC).[reply ]

Sorry for not replying but this all went down in the middle of the night my time. —David Eppstein (talk) 17:46, 12 January 2025 (UTC) [reply ]

Sorry for calling your page random, David, but I think you know what I meant! Bishonen | tålk 09:38, 13 January 2025 (UTC).[reply ]

I know that Wikipedia bans don't have cross-project reciprocity, but it seems that last month DrBogdan decided to recreate his blanked userpage on the Luxembourgish wikiproject, which he otherwise doesn't edit on (or, given the English bio, I assume speak). It's pretty clear that he's going to keep systematically using wikipedia as a webhost and trying to find ways to dance around the rules (like linking to diff copies of his userpage from his Livejournal so he can still use Wikipedia as a host). Is there a venue for more pan-wiki concerns to be raised here, if this is even sufficient to address? Because I'm not even 100% sure if I can raise this at the Luxembourgish wikiproject or here. Warrenᚋᚐᚊᚔ 14:23, 12 January 2025 (UTC) [reply ]

There is a process for blocking editors from all languages: Wikipedia:Global blocks. It involves a proposal and discussion on meta but they're unlikely to agree to it until we already have a record of behavior leading to a block on multiple languages, not just the start of a pattern. —David Eppstein (talk) 17:48, 12 January 2025 (UTC) [reply ]

It can't hurt to raise the issue over at the Luxembourgish site, surely. XOR'easter (talk) 21:28, 12 January 2025 (UTC) [reply ]

That's where it would have to be raised, to do anything on that site, unless a global block can be imposed. —David Eppstein (talk) 22:35, 12 January 2025 (UTC) [reply ]

I did a bit more digging and since his ban he's been maintaining his "profile" across multiple wikis where the only edit history he has is maintaining said profile, mostly since his CBAN. He's had his page at the Luxembourgish wikiproject blanked by an admin, I think a global block may be warranted since there's persistent WP:NOTWEBHOST/WP:PROMO issues. Warrenᚋᚐᚊᚔ 11:07, 13 January 2025 (UTC) [reply ]

Can you please semi Wikipedia talk:VRT noticeboard - FlightTime (open channel) 08:30, 13 January 2025 (UTC) [reply ]

The editor in question has been blocked as an LTA by User:Johnuniq. If we start seeing IP-hopping vandalism it can be semi'd but I suspect more likely is they would find another vandalism target. —David Eppstein (talk) 08:33, 13 January 2025 (UTC) [reply ]

Hmm, I didn't look far back enough in the history to see the IP-hopping already. Semi'd for a couple days. I don't think the timeframe of the vandalism justifies much longer than that. —David Eppstein (talk) 08:36, 13 January 2025 (UTC) [reply ]

Thank you again for your quick response. Cheers, - FlightTime (open channel) 08:43, 13 January 2025 (UTC) [reply ]

Many of the standard and highly viewed places where an IP can post have been semi protected for a week or so recently. It’s an LTA with nothing to do. Johnuniq (talk) 09:39, 13 January 2025 (UTC) [reply ]

Hello, thank you for fixing harvtxt errors I failed to catch! Instead of substituting the ref templates, I might recommend the use of {{sfn whitelist}}, so that any updates to the reference templates in the future will propagate. (See example, the whitelist URLs are found by clicking the harvtxt link.) Tule-hog (talk) 01:29, 15 January 2025 (UTC) [reply ]

Following deletion in a 2009 AfD, an article on Win Wenger was recreated and is now nominated for deletion at Wikipedia:Articles for deletion/Win Wenger (2nd nomination). I am notifying all participants in the original AfD. Dclemens1971 (talk) 14:56, 16 January 2025 (UTC) [reply ]

Hi David,

I have been doing a clean up of consulting firms lately and I came across Pantheon Macroeconomics. Which I think is lacking in notability since the sources I see are all about quoting what it publishes rather that about the firm itself. I noticed the creator is an SPA that only makes edits related to the firm.

I see the other articles created are Ian Shepherdson and Samuel Tombs and I'm unsure about the notability. They are economists but they are working in a private sector. So I want to ask should we treat them as academics or not? I see sources have mentioned them but its more of this person said this during this year and he previously had a good track record. I'm not sure if that's enough to count towards notability. Primary sources from the firm will not be counted of course. - Imcdc Contact 06:43, 17 January 2025 (UTC) [reply ]

They aren't ranked among top academic economists at https://ideas.repec.org/top/top.person.all.html so I suspect if there is notability there it is not as an academic. —David Eppstein (talk) 06:46, 17 January 2025 (UTC) [reply ]

Hi David. Do you think the Moran Medal is prestigious enough to qualify for point 2 of WP:NACADEMIC? You generally seem well-informed about this kind of thing. GanzKnusper (talk) 15:58, 17 January 2025 (UTC) [reply ]

The Australian Academy of Science categorizes its awards into four levels, "premier", "career", "mid-career", and "early-career". The Moran Medal is one of the lowest level early-career ones [4]. So my feeling is that although it is a step towards notability it is probably not enough by itself. —David Eppstein (talk) 18:34, 17 January 2025 (UTC) [reply ]

Fab, thank you. GanzKnusper (talk) 23:28, 17 January 2025 (UTC) [reply ]

— Benison (Beni · talk) 08:27, 19 January 2025 (UTC) [reply ]

Are these journals "reliable sources"? Do you have any objections, complaints, comments, etc. concerning these journals?

INTEGERS - Electronic Journal of Combinatorial Number Theory

Missouri Journal of Mathematical Sciences

Linear Algebra and its Applications

Sugaku

Japanese Journal of Mathematics

Journal of the Mathematical Society of Japan 45.50.225.84 (talk) 17:17, 23 January 2025 (UTC) [reply ]

My usual legitimacy test for a mathematics journal is whether they are indexed by MathSciNet or zbMATH. All of these are fully indexed in both, so they are legitimate mathematics journals. —David Eppstein (talk) 17:45, 23 January 2025 (UTC) [reply ]

Hi there, I'm pleased to inform you that I've begun reviewing the article Grid bracing you nominated for GA-status according to the criteria. This process may take up to 7 days. Feel free to contact me with any questions or comments you might have during this period. Message delivered by ChristieBot, on behalf of Noleander -- Noleander (talk) 20:07, 24 January 2025 (UTC) [reply ]

Sir, in the Orient, we have a saying: 'impartiality and selflessness'. As a mathematician, you would appreciate the beauty of theorems. Thus, you would understand the elegance of the Eight circles theorem that I recently submitted for publication. If I were in your position, I would focus on the content of the article rather than who created it. If you delete it, others may hesitate to submit their work in the future, fearing a similar outcome. Over a decade ago (2014), due to a lack of understanding of Wikipedia's policies, I created articles related to myself, for which I was subsequently blocked. However, Wikipedia also allows authors to write about themselves as long as they maintain a neutral perspective. Therefore, I kindly request that you reconsider your decision regarding the eight-circle theorem. Although my name is associated with the theorem due to my initial discovery, there have been numerous related studies published in various sources.

Best regards Dao Thanh Oai — Preceding unsigned comment added by 2401:D800:2D1:EA10:195D:186F:C960:D902 (talk) 01:39, 25 January 2025 (UTC) [reply ]

If you are willing to stop your relentless self-promotion and edit other topics, an unblock request might reasonably be considered through the proper channels. Evading the block and creating sockpuppets to self-promote, on the other hand, can only get a negative response here. —David Eppstein (talk) 02:33, 25 January 2025 (UTC) [reply ]

Please accept my apologies for the delayed response. The past few days coincided with the Lunar New Year festival in Vietnam, during which time I was not using my computer.

From the perspective of an en.wiki administrator, your assessments of me are entirely accurate, and I have no counter-arguments to offer. It is often challenging to find common ground when individuals hold differing viewpoints. I hope you will consider removing the ban on my account so that I can occasionally contribute to the common cause in the field of classical geometry.

I hope that you, in your capacity as an expert and mathematician, consider undertaking the compilation of the Eight circles theorem, regardless of whether it bears any connection to my name. Finally, I extend my sincere gratitude to you. I also expressed my gratitude to you by translating the article about you into vi.wiki ten years ago David Eppstein.

Best regard Dao Thanh Oai — Preceding unsigned comment added by 117.6.160.160 (talk) 04:38, 3 February 2025 (UTC) [reply ]

--Lajmmoore (talk 08:56, 26 January 2025 (UTC) via MassMessaging[reply ]

So in this edit you did a reasonable thing that had unreasonable consequences, at least at Coxeter group, where (as Eisenstein Integer noticed today) it ended up transcluding the entire article List of polygons, polyhedra and polytopes into the other article [5], because someone set it up to do that (basically as a template substitute or something?). Is there any way to check whether this problem might be more widespread? --JBL (talk) 20:34, 26 January 2025 (UTC) [reply ]

There was another one in Petrie polygon. This search suggests that those were the only ones. —David Eppstein (talk) 20:39, 26 January 2025 (UTC) [reply ]

Great, thanks! JBL (talk) 00:08, 31 January 2025 (UTC) [reply ]

The article Grid bracing you nominated as a good article has passed ; see Talk:Grid bracing for comments about the article, and Talk:Grid bracing/GA1 for the nomination. Well done! If the article is eligible to appear in the "Did you know" section of the Main Page, you can nominate it within the next seven days. Message delivered by ChristieBot, on behalf of Noleander -- Noleander (talk) 04:45, 28 January 2025 (UTC) [reply ]

Hello, Professor David Eppstein! I'm feeling better, after some days more than two weeks, but a lot better, and I wanted to create an article about the book Visual Complex Analysis, by Tristan Needham. There are enough reviews, but it currently is a redirect to the biography. I am in doubt if I should turn the redirect into an article (a stub...) or expand the information about the book in the biography itself. Which of the two possibilities would you think is the best in this case? Maybe both things? Best regards! MathKeduor7 (talk) 12:30, 29 January 2025 (UTC) [reply ]

I think I'll expand the biography! MathKeduor7 (talk) 12:31, 29 January 2025 (UTC) [reply ]

Psychiatrist advised me to stay away from the Internet for a while... I'll try to follow his recommendation (I'll try to improve the article about Needham when the mania vanishes...). Best regards! MathKeduor7 (talk) 01:07, 30 January 2025 (UTC) [reply ]

Increasingly I am encountering editors who clearly don't understand the very concept of what a citation is and what it does. The most common error is to "cite" an example of usage but it goes on. So I wondered if perhaps [wearing your prof hat] you know of a really really basic guide to the principle of citations? I expected Help:Referencing for beginners to explain the concept before leaping into the detail of how to do it, but no. (So I added a "further reading" section containing

• Yale Poorvu Center for Teaching and Learning. "Why Cite Sources in Your Academic Writing?". Yale.edu. Retrieved 2025年01月23日.

but I worry that it is pitched at rather too high a level for many of our confused editors.) Or maybe you've been itching to write a Wikipedia Essay that we can direct the confused to read . What do you think? JMF (talk) 00:30, 30 January 2025 (UTC) [reply ]

I don't really know of a good off-wiki source for this but I haven't really looked for one. We also have Wikipedia:Scientific citation guidelines but that's more specialized and again probably assumes that readers know what citations are supposed to be used for. —David Eppstein (talk) 00:42, 30 January 2025 (UTC) [reply ]

No worries, I just hoped that you might have come across this painfully often with freshmen that you'd have something ready to hand. Even our Citation article is mostly about citation styles, it just assumes that readers are already familiar with the principle. Oh well, as freeloading on you is not an option, I'll have to go on a hunting trip. JMF (talk) 11:06, 30 January 2025 (UTC) [reply ]

Sorry, I don't generally teach the freshman-level classes and if I did it would be discrete math or Boolean algebra. —David Eppstein (talk) 18:06, 30 January 2025 (UTC) [reply ]

Perhaps you might try pondering why the abbreviation for your link is "WP:GHETTO"

Come on, man. Disagree with me and comment, but don’t be disrespectful and condescending like this. No, my view is not due to a failure on my part to "try pondering". This was really disappointing. ꧁Zanahary ꧂ 01:43, 2 February 2025 (UTC) [reply ]

So your mind is closed. How sad. —David Eppstein (talk) 02:02, 2 February 2025 (UTC) [reply ]

Oh my god, I remember you! I think I was confusing you with Doug Weller, from whom rudeness would have been really disheartening. I no longer care. ꧁Zanahary ꧂ 02:05, 2 February 2025 (UTC) [reply ]

Hello Prof. David Eppstein. As was explained in my accompanying comment, my clarification request on the "Greedoid" article was meant to ask whether the ground set of the greedoid in that precise sentence should actually be finite ? Dijkschneier (talk) 19:09, 2 February 2025 (UTC) [reply ]

The article earlier talks about finite set systems, and I think everything here is intended to be finite. But how is that relevant to where you put the tag, on a definition of a basis that is immediately clarified? —David Eppstein (talk) 19:28, 2 February 2025 (UTC) [reply ]

My addition to the page "Feedback vertex set": "The feedback vertex set number of a graph is the size of a smallest feedback vertex set, which for a directed graph is the same as its cycle rank."

You: "WTF no it isn't. Maybe you're thinking of the undirected case?"

I'm not really sure what you mean by this. The cycle rank is broadly speaking "how close a digraph is to a directed acyclic graph (DAG)", and a FVS can be for directed or undirected, so I'm not sure what you are referring to. As far as whether these metrics are the same for a directed graph (FVS number *for a directed graph vs. cycle rank), they do seem to refer to the same thing as far as I can tell.

Cycle rank:

• If G is acyclic, then r(G) = 0.
• If G is strongly connected and E is nonempty, then

${\displaystyle r(G)=1+\min _{v\in V}r(G-v),,円}${\displaystyle r(G)=1+\min _{v\in V}r(G-v),,円} where ⁠${\displaystyle G-v}${\displaystyle G-v}⁠ is the digraph resulting from deletion of vertex v and all edges beginning or ending at v.

• If G is not strongly connected, then r(G) is equal to the maximum cycle rank among all strongly connected components of G.

Is this process not equivalent to deleting the least amount of vertices necessary to make a DAG? BagLuke (talk) 00:56, 3 February 2025 (UTC) [reply ]

No it is not.

For example a graph with k disjoint cycles (one per strongly connected component) will have cycle rank one but feedback vertex number k. A graph with k cycles all hanging off one central cycle will have cycle rank two (remove one vertex to kill the central cycle, then treat each remaining strongly connected component separately) but feedback vertex number again k. —David Eppstein (talk) 01:17, 3 February 2025 (UTC) [reply ]

Ahh, I see, I misremembered the last rule, where cycle rank is equal to the maximum cycle rank among all strongly connected components of G, not the sum total of the cycle ranks of each connected component. Thanks for the clarification! BagLuke (talk) 02:03, 3 February 2025 (UTC) [reply ]

Thanks for recent changes to Square, adding sources about the non-Euclidean versions. I hadn't known that people used the name "square" for equiangular and equilateral quadrilaterals. You might also consider adding source(s) / elaboration to Rectangle § Other rectangles, if you have some. (I also didn't realize that such shapes were called "rectangles" in those contexts – while they are a natural analog of Euclidean rectangles, they don't have right angles, so it seems like a bit of a misnomer.)

It might even be worth adding a new article calledNon-Euclidean quadrilateral or similar, discussing these various types of shapes and their properties. I added a section with a picture about spherical parallelograms at Lexell's theorem § Spherical parallelogram, and there's also some relevant information at Saccheri quadrilateral and Lambert quadrilateral. –jacobolus (t) 23:50, 3 February 2025 (UTC) [reply ]

Yes, the case for calling regular quadrilaterals "squares" seems clearer to me than for rectangles, but even so some authors balk at it. I think square could use a lot more sourcing in other places as well. I don't have convenient sources squirreled away; I had to search for them for the non-Euclidean squares, and I imagine it might be harder to find high-quality sourcing for these supposed non-Euclidean rectangles. —David Eppstein (talk) 23:56, 3 February 2025 (UTC) [reply ]

I have to run for now, but here are a few sources besides Maraner:

JSTOR 10.4169/mathhorizons.23.4.8, doi:10.1080/07468342.2008.11922271, doi:10.1559/152304009788188781. –jacobolus (t) 04:15, 4 February 2025 (UTC) [reply ]

I don't have convenient sources squirreled away... or, one might say, squarelled away. I'll see myself out now. XOR'easter (talk) 04:36, 4 February 2025 (UTC) [reply ]

Thanks for putting work into Square. It's definitely the kind of page where we ought to be putting our best foot forward. XOR'easter (talk) 17:03, 8 February 2025 (UTC) [reply ]

Aside: it doesn't help with non-Euclidean case but (since you were working on Square) about planar quadrilaterals I found Josefsson (2016) "On the classification of convex quadrilaterals" JSTOR 44161706 to be a pretty nice classification of quadrilaterals, with clear discussion and a pleasantly symmetrical diagram of their relationships. –jacobolus (t) 08:22, 10 February 2025 (UTC) [reply ]

Thanks. My go-to source for this classification has been Usiskin & Griffin but that one looks good too, and maybe more widely accessible. Square already cites a different Josefsson paper but not that one. —David Eppstein (talk) 08:26, 10 February 2025 (UTC) [reply ]

You reverted the definition of "face" in convex set, Special:Diff/1273777259, but I think it was correct. The definition was from Rockafellar's standard book. A line segment F interior to a triangle C is not a face of C by this definition, because each point in F is contained in some line segment between two points of the triangle that are not on F. If you agree, please un-revert. Thanks. BTotaro (talk) 01:06, 4 February 2025 (UTC) [reply ]

It's based on MOS:UL and MOS:OL. RJANKA (talk) 17:26, 8 February 2025 (UTC) [reply ]

Neither of those justifies adding off-topic distracting junk to the middle of a sentence, making the sentence hard to follow because it is so long and off-topic, in a mathematics article. And WP:BRD demands you stop trying to ram your edits through and start trying to build consensus for your edits on the article talk page instead. —David Eppstein (talk) 18:01, 8 February 2025 (UTC) [reply ]

Evening @David Eppstein: Do you think this women is notable Draft:Lisa Genzel? I was checking the Wikipedia:WikiProject Women in Red/Drafts and that came up. scope_creep ^Talk 18:35, 12 February 2025 (UTC) [reply ]

Looks kind of borderline to me. Mid-career (associate professor) with mid-career major funding (VIDI). Neurobio is a very high-citation field so although her citation counts look good I don't know whether they're good enough. User:JoelleJay might have a better idea. —David Eppstein (talk) 18:39, 12 February 2025 (UTC) [reply ]

Thanks for the ping! In general, for neurobio, I would be looking for an H-index of 40+ on Scopus (hers is 25) if I wanted to include someone in my user page list, though I do have a higher threshold there. I'll take a look at her overall metrics compared to her coauthors', but my initial impression is that she's not yet at the level where her research stands out as notable. JoelleJay (talk) 20:57, 12 February 2025 (UTC) [reply ]

I will keep that in mind re:neurobio h-index value. Thanks. scope_creep ^Talk 13:05, 13 February 2025 (UTC) [reply ]

Dear Prof. Epstein,

I am not a Wikipedia specialist; apology in advance if I do not satisfy the "rules" for a post like this.

My name is Isaac Malitz (AKA Richard Malitz). There was a Wiki article for my name, this was removed. Also, references to me in the article Positive Set Theory were removed.

Having studied your comments above about these exclusions, I think I understand that the two articles ran up against some new formal requirements which resulted in the exclusions. I think that these results were "accidental" in the sense that [a] I am considered a fairly important figure in both Set Theory and Contemporary Music; and [b] I am considered a seminal figure in the history of Positive Set Theory, have been cited and honored appropriately, and my work has certain unique and extremely important aspects not reported in the current article on Positive Set Theory. 64.98.211.25 (talk) 00:32, 13 February 2025 (UTC) [reply ]

It was not a new formal requirement. It was an old and not very formal requirement for notability as a scholar and researcher that the article was not even close to meeting. Also, see our policy on autobiographies. You should not be writing an article about yourself. —David Eppstein (talk) 00:40, 13 February 2025 (UTC) [reply ]

The article on me was not autobiographical. Someone else wrote it, someone I don't know, and I had absolutely no role in writing it. Same re the article on Positive Set Theory. 64.98.211.25 (talk) 00:46, 13 February 2025 (UTC) [reply ]

BTW, if the materials violated "old" guidelines, tell me how they were approved originally!!

Why don't you check the provenance of those articles; if their provenance is legit, then perhaps your decisions should be examined. I don't wish to be contentious here; but you are the one who accused me of trying to slip in an autobiography. Which I did not do. Period. Check the authors, ask them 64.98.211.25 (talk) 00:52, 13 February 2025 (UTC) [reply ]

If you can provide me some specific guidance how to "repair" the above situation, I think both articles will be restored/fixed.

Here is a quick outline:

[1] Article on Isaac Malitz: Malitz was arguably the creator of Positive Set Theory in its original "topological" mode. He is also President and Board Chair of Monday Evening Concerts (see Wiki article on this), numerous citations and references. MEC considered one of the leading contemporary music series in the world, was just profiled in an article in The New Yorker.

[2] Article on Positive Set Theory: Malitz the seminal figure. Cited as one of the key contributors re Set Theory with a Universal Set, in book by the same name by Prof. Thomas Forster. Forster's book considered the key book on the subject; my work is ranked above work by Alonzo Church. Citations in various journal articles. From a technical point of view: Positive set Theory has 2 formulations, one syntactic, the other topological. The topological version was developed first, and by me. It is philosophically very important because of its close relationship with Liebniz metaphysics (Identity of Indiscernibles, Principle of Plenitude0 64.98.211.25 (talk) 00:43, 13 February 2025 (UTC) [reply ]

You can repair the article by waiting for a few years until Malitz's accomplishments are better recognized in the published literature and then incorporating that recognition into a new article. I don't think there is any hope of a quicker thing to do. —David Eppstein (talk) 00:51, 13 February 2025 (UTC) [reply ]

I think I want to appeal your decision. How do I do that? ALSO, re the bio article, there are new accomplishments, going back about 8 years. 64.98.211.25 (talk) 00:54, 13 February 2025 (UTC) [reply ]

You can appeal at WP:DRV if you think the process was performed incorrectly. Appeals based purely on your disagreement with the opinions and outcome are unlikely to be effective. —David Eppstein (talk) 01:08, 13 February 2025 (UTC) [reply ]

Do Wikipedia have the article about faithfully embedding on an orientable sphere in graph theory? I have found in this source [6], and as a user who cannot fully understand what it means, can you explain the first theorem in a simple way, especially on the polyhedral graph's examples? Dedhert.Jr (talk) 05:36, 13 February 2025 (UTC) [reply ]

It's about realizing the abstract combinatorial symmetries of the graph as topological symmetries of the embedding of the graph. For a simple example, consider the complete graph on four vertices, ${\displaystyle K_{4}}${\displaystyle K_{4}}. It has ${\displaystyle 4!=24}${\displaystyle 4!=24} symmetries, all permutations of its four vertices. But if you draw it in the plane as a square with its diagonals, you will only get eight of these symmetries: no matter how you stretch or warp the plane topologically, the diagonal pairs will stay opposite each other. To realize all 24 symmetries, you can instead draw it on the sphere as a spherical tetrahedron. —David Eppstein (talk) 05:53, 13 February 2025 (UTC) [reply ]

Oh, that is intuitively easy, yet technically hard to understand. Graph embedding seems to be the good spot to include it, no? Dedhert.Jr (talk) 06:22, 13 February 2025 (UTC) [reply ]

Maybe. Similar ideas are mentioned at Graph drawing#Quality measures (third bullet) and Canonical polyhedron (which realizes all combinatorial symmetries of a polyhedral graph as geometric symmetries, not merely as topological symmetries). —David Eppstein (talk) 06:35, 13 February 2025 (UTC) [reply ]