User talk:David Eppstein/2012b

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Speedy Keep
Your speedy keep here claimed that the arguments were the same. The argument in the current AfD is that while the academic may be notable there is a complete lack of sources with which to create an article, from the responses in the AfD it can be seen that there is a complete lack of reliable independent sources to create an article with. This was not addressed in the first AfD. IRWolfie- (talk) 15:21, 4 April 2012 (UTC)


 * Are you going to address my concerns or do I need to take it to DRV? IRWolfie- (talk) 17:27, 4 April 2012 (UTC)
 * DRV seems appropriate if you are still not convinced by the two AfDs. —David Eppstein (talk) 18:47, 4 April 2012 (UTC)
 * The first AfD was closed properly, your close was inappropriate because the issues raised were different than the first AfD yet you closed it stating that the arguments were the same. Please point where the issue of the non-existence of sources to use in the article was raised in the first AfD. IRWolfie- (talk) 18:53, 4 April 2012 (UTC)

You reverted my revert of a bold addition on the article but you have not commented on the talk page, I suggest you do so per WP:BRD. IRWolfie- (talk) 17:17, 4 April 2012 (UTC)
 * I left an edit summary that says all I care to say about the matter. —David Eppstein (talk) 17:19, 4 April 2012 (UTC)

Re 24968_Chernyakhovsky
Hi, please leave the article alone. There are literally hundreds of these added from the ISEF winnings, it is unfair to delete just this one. Thanks. 18.96.6.177 (talk) 04:31, 12 April 2012 (UTC)
 * Please see WP:WAX. —David Eppstein (talk) 04:33, 12 April 2012 (UTC)
 * Excuse me, but there are *hundreds* of these, and they weren't making anyone mad until Alexander Chernyakhovsky appeared. These are separate issues. Please do no pick on on article just because of your opinion on another. If you are going to do so, you have to delete 24977 Tongzhan and 24549 Jaredgoodman and all the rest like it.18.96.6.177 (talk) 04:38, 12 April 2012 (UTC)
 * It's true that I only do stuff to pages that I find out about — who can do otherwise? I'll be happy to prod those other two or as many others like them as you find but maybe at this point we should wait to see how the AfD goes. —David Eppstein (talk) 04:41, 12 April 2012 (UTC)
 * Then I am confused why you care about this one.18.96.6.177 (talk) 04:51, 12 April 2012 (UTC)
 * Because I found out about this one. —David Eppstein (talk) 04:52, 12 April 2012 (UTC)
 * Then why did you say something like "And delete his little dog", is that supposed to be funny?04:57, 12 April 2012 (UTC) — Preceding unsigned comment added by 18.96.6.177 (talk)
 * You never watched The Wizard of Oz? —David Eppstein (talk) 05:11, 12 April 2012 (UTC)
 * Apparently not.18.96.6.177 (talk) 05:23, 12 April 2012 (UTC)

R. W. H. T. Hudson
Prof. Eppstein, thank you for moving correctly Ronald Hudson's article. Giftlite (talk) 17:00, 12 April 2012 (UTC)

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DYK for Emanuels Grīnbergs
Casliber (talk · contribs) 00:04, 14 April 2012 (UTC)

WP:COPYVIO
In the AFD Articles for deletion/Joachim Weickert you stated that you "didn't see much evidence of copyvio". Please cast your eye upon Talk:Joachim Weickert. If you don't see a problem, then please read Copyright violations. You might also wish to read the information page Copy-paste Much of the content of the article at the time of the AFD nomination was a violation of the Wikipedia terms of use. Thanks. Edison (talk) 05:12, 19 April 2012 (UTC)
 * Well, I agree that the comparison on the talk page looks too closely paraphrased for my taste, but there are only so many ways one can write "he got degrees X and Y and worked at universities Z and W." —David Eppstein (talk) 05:18, 19 April 2012 (UTC)

DYK for Mictyris guinotae
Materialscientist (talk) 16:10, 20 April 2012 (UTC)

DYK for Danièle Guinot
Materialscientist (talk) 16:10, 20 April 2012 (UTC)

º vs °
I considered users who type the degree sign as $$\circ$$ as lamers, but only before spotting your "180º rotation". Incnis Mrsi (talk) 09:47, 23 April 2012 (UTC)
 * Sorry, but ° and º look too similar to each other and are right next to each other on the keyboard (option-shift-8 vs option-0); it's hard to remember which is which. —David Eppstein (talk) 15:24, 23 April 2012 (UTC)

Disambiguation link notification for April 23
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 * Stupid bot, that one was deliberate, as indicated by the dab needed tag. —David Eppstein (talk) 15:22, 23 April 2012 (UTC)

DYK for Telephone number (mathematics)
Orlady (talk) 16:09, 26 April 2012 (UTC)

Maximum weighted average
Thought it might amuse you that after considerable discussion about a question on the Math Reference Desk today, User:Modocc found a 1995 paper of yours that answers it: Reference desk/Mathematics. Regards, Qwfp (talk) 21:45, 30 April 2012 (UTC)
 * Thanks for letting me know. That's one of my more obscure ones... —David Eppstein (talk) 21:49, 30 April 2012 (UTC)

This is for you. Listen carefully.
http://www.youtube.com/watch?v=gfebdiErvDo — Preceding unsigned comment added by 86.24.46.135 (talk) 22:59, 2 May 2012 (UTC)

Dead link in article 'Rule 184'
Hi. The article 'Rule 184' has a dead link that could not be repaired automatically. Can you help fix it?

Dead: http://www.leitl.org/docs/density.ps.gz
 * You added this in May 2007.

This link is marked with Dead link in the article. Please take a look at that article and fix what you can. Thank you!
 * The bot checked The Wayback Machine and WebCite but couldn't find a suitable replacement.

PS- you can opt-out of these notifications by adding to your user page or user talk page. BlevintronBot (talk) 06:07, 6 May 2012 (UTC)
 * ✅. Thanks for the heads-up. —David Eppstein (talk) 06:30, 6 May 2012 (UTC)

DYK for Tina Mion
Graeme Bartlett (talk) 00:04, 11 May 2012 (UTC)

Your continuing subversive anti-Western and anti-Ukrainian edits and reverts
David Eppstein, you serve your anti-Western and anti-Ukrainian Russian master, Vlad Putine, very well.

Your continuing anti-Ukrainian edits and reverts cannot be ignored.

Please familiarize yourself with Wikipedia policies before resorting again to your disruptive and subversive editing of Ukraine-related Wikipedia articles. Wikipedia policies may seem difficult for you to understand and to comply with, David Eppstein. However, believe me, this is just in the beginning. Please do not hesitate to ask other editors, including myself, if you need any explanations or clarifications. I would also recommend to you to use talk pages of pro-Western Ukrainian editors, asking questions and getting answers about Ukraine, BEFORE attempting to contribute the Ukraine-related Wikipedia articles.

Please do not resort again to your past habit of biased anti-Western edits about the Ukrainian matters.

. — Preceding unsigned comment added by 76.102.173.102 (talk) 06:12, 12 May 2012 (UTC)


 * Please make it stop! Kiefer  .Wolfowitz  21:35, 17 July 2012 (UTC)

Courcelle's
Thank you. The logical statement does, however, run over the edge on my browser. I think it needs to have line breaks between the conjuncts and disjuncts but not knowing the math syntax, I should leave that to you. History2007 (talk) 22:20, 13 May 2012 (UTC)

A barnstar for you!

 * Thanks! Glad I could help. —David Eppstein (talk) 03:28, 14 May 2012 (UTC)

TB
benzband ( talk ) 20:38, 18 May 2012 (UTC)

Notability of Academics
I replied to your comments on the talk page of WP:PROF. NJ Wine (talk) 02:28, 23 May 2012 (UTC)

DYK for Albert Brahms
Graeme Bartlett (talk) 08:04, 25 May 2012 (UTC)

proof outline
It is possible to write down this formula:
 * $$\sum_{k=0}^n k^2=\sum_{k=0}^{n-1} \sum_{i=k+1}^n i $$

This is an alternative way to group the sum of the squares: to quote an example, we assume n=5:
 * $$ 0^2+1^2+2^2+3^2+4^2+5^2 = $$
 * $$ 1+2+3+4+5 +$$
 * $$ 2+3+4+5 +$$
 * $$ 3+4+5 +$$
 * $$ 4+5 +$$
 * $$ 5 $$

In this representation the number five is summed 5 times, the number 4 is summed 4 times, and so on, until zero. After that, it is possible to use this result to solve the summation:
 * $$\sum_{i=k}^{n} i= \frac{n(n+1)}{2} - \frac{k(k-1)}{2}$$

The main formula is equivalent to
 * $$\sum_{k=0}^n k^2=\sum_{k=0}^{n-1} [\frac{n(n+1)}{2} - \frac{k(k+1)}{2}]$$

After some agebraic manipulation it is possible to obtain:
 * $$\frac{3}{2}\sum_{k=0}^n k^2=\frac{n^2(n+1)}{2} - \frac{n(n-1)}{4}+ \frac{n^2}{2}$$

This is equivalent to the desired formula.

86.24.46.135 (talk) 18:47, 29 May 2012 (UTC)

File:Steinhaus-Johnson-Trotter-Permutohedron.svg
Hi David. I don't really get your illustration of the Steinhaus–Johnson–Trotter algorithm. You have labelled your graph with the permutations from the Cayley graph and not with those from the permutohedron. Is this really what you have intended? I created the file on the right because that's how I understand "Hamiltonian path in the permutohedron". Lipedia (talk) 17:05, 30 May 2012 (UTC)


 * The algorithm works by swapping the values of elements in adjacent positions of the permutation, so we need the vertices of the graph to be labeled in such a way that this kind of swap corresponds to an edge. The Cayley graph has that property; the permutohedron doesn't. But the graphs are isomorphic (related to each other by inverting the labels) so the algorithm does indeed also find a Hamiltonian path in a graph isomorphic to the permutohedron. —David Eppstein (talk) 17:21, 30 May 2012 (UTC)

Indeed, your illustration is correct. To me the sentence
 * "Consecutive permutations in the sequence generated by the Steinhaus–Johnson–Trotter algorithm have numbers of inversions that differ by one, forming a Gray code for the factorial number system."

was misleading, because the path in the permutohedron is a textbook example of a "Gray code for the factorial number system" - but I wouln't say that about the path in the Cayley graph. There is e.g. a change from inversion vector (0,0,0,2) to (0,0,1,0). Is that a change in a Gray code?! See my change. Lipedia (talk) 12:36, 31 May 2012 (UTC)

Block me!
You can block me whenever you want. When the block will expire I will post my proof again. Forever. If you block me forever, I will ask somebody also to post my proof for me. Forever.

I think it's not fair what you did on "square pyramidal number page". Do you think it's fair to make a content remove only because you decided that it's not interesting? A civilized person would discuss it in the discussion page. I'm not dropping this. — Preceding unsigned comment added by 86.24.46.135 (talk) 15:48, 1 June 2012 (UTC)
 * I've taken this to WP:ANI. —David Eppstein (talk) 16:10, 1 June 2012 (UTC)
 * I think 86.24.46.135 is asking for a permanent ban. And I hope he gets one. Maproom (talk) 19:25, 2 June 2012 (UTC)

Indian mathematics
Hello, I am a user very active in the Good Article nominating system. I often look and scout for articles that could pass as GAs. I was sifting through WikiProject Mathematics, and found this article. You seem to be the editor who has has the most recent edits done, and I was wondering, do think the article is ready to go under a GA review. If so, Great! If not, what could be done to improve it. I am really exuberant when an article I nominate becomes a GA, and would like for this one to. Please, help this article become a GA. Thanks mate! Oakley77 (talk) 16:45, 3 June 2012 (UTC)
 * I don't think I'm really the right person to ask about that article — my edits haven't been very major in comparison to some others, and I think others such as are more knowledgeable. But the biggest problem with  that article is that it's a politically contentious subject — you will run into a three-way conflict between proponents of India who wish to puff up their (significant) accomplishments even further, others who wish to diminish them, and others who wish to strive for an accurate portrayal without political bias.

Talkback
 Я ehevkor ✉  01:19, 12 June 2012 (UTC)

Travis Turner
Hi David,

Regarding Travis Turner, I see he still does not have a page and I am a big fan of his films/music and want to see a proper page created for him...I am not sure how to create the article properly myself is there a possibility of you creating it?, or helping me get it created? As The Princess For Christmas is notable.
 * I have no idea who Turner is, so I think it would helpful to find someone to help who does know of him. But I think the most important thing is to start with reliable sources (e.g. newspaper stories about Turner found in Google news search), cite them properly, and only put into the article the information you've found in those sources. That way it should be obvious to other editors that he's notable. —David Eppstein (talk) 23:42, 13 June 2012 (UTC)

Acyclic graph
If the only difference between the kinds of graphs that can be called acyclic is the direction of the graphs and cycles, prehaps this is a suitable topic for a short article delineating these distinctions and explaining why all of these types are nonetheless "acyclic" graphs. This would also resolve the current disambig link to this title at Fat tree. Cheers! bd2412 T 17:25, 15 June 2012 (UTC)
 * Those three classes of graphs are not very similar to each other. I think a disambiguation page is a reasonable solution. As for the fat tree link, it is clearly about the undirected case. —David Eppstein (talk) 18:00, 15 June 2012 (UTC)
 * If they are suitably distinct that incoming links can be kept clear, then I have no objection to continued disambiguation. Nevertheless, as a non-expert in the area, they seem to be variations on a theme. After all, what is it that makes them all "acyclic graphs"? Just a thought. bd2412  T 18:56, 15 June 2012 (UTC)
 * They all have forbidden graph characterizations where the forbidden subgraph is something that can be called a cycle. But those are not the only ways of characterizing these graphs, and the details of what that something is makes them quite different from each other. —David Eppstein (talk) 19:02, 15 June 2012 (UTC)
 * It's all Greek to me, but I trust your judgment in the field. Cheers again! bd2412  T 19:11, 15 June 2012 (UTC)

DYK for Wall poems in Leiden
Casliber (talk · contribs) 16:02, 16 June 2012 (UTC)

Zemgus Girgensons
Would it be possible to unsalt the Zemgus Girgensons article, as in three days the 2012 NHL Entry Draft will take place, and Girgensons is more than likely to be selected in the first round, thus passing the WP:NHOCKEY criteria. Surely there will be contributors willing to add some information on his article straight afterwards. Gragox (talk) 13:50, 19 June 2012 (UTC)
 * Ok, done. —David Eppstein (talk) 15:12, 19 June 2012 (UTC)

David Eppstein article
I saw you removed Category:American Jews from your biography article on the grounds that it was unsourced and untrue. Not that you are obligated to provide any, but do you have any reason to believe it is not true? Genetic test or something? Forgive me if it is a rude question, it seemed an obvious conclusion from the surname and photograph, but I did not mean to insert a libelous or offensive label. On a related matter I see that you link your personal page and blog from your user page. If someone in industry were editing their own biography article, discussing their profession, and linking more detailed off-wiki pages about themselves and places of employment, would this be considered less appropriate than for someone in academia? It seems ok to me; I am not objecting. Thanks for your time. Obotlig ☣ interrogate 07:55, 20 June 2012 (UTC)
 * Jewish descent runs through the mother's line and my mother's ancesters were all Christian. I was baptised shortly after birth. My marriage ceremony was in a Unitarian church. I could go on. In any case, it is inappropriate to add religion categories to biographical articles when there is no evidence that religion is important to the subject; see WP:CAT/R. —David Eppstein (talk) 14:05, 20 June 2012 (UTC)
 * I believe the category is an ethnic description. There is nothing at WP:CAT/R and I couldn't quickly find the relevant policy or guideline article. What the Jewish culture or religion considers to convey membership in the race, ethnic group or religion is not relevant to someone being substantially of an ethnic background and obviously so, by the normal standards of English readers, western anthropologists, etc. At any rate, thanks for the information. It seems to me if someone has a "Jewish" surname and visually appears to be an Ashkenazi Jew they should be classified as such, and would be by the overwhelming majority of native English speakers. But it's more important what you consider an offensive label. Obotlig ☣  interrogate 14:29, 20 June 2012 (UTC)
 * I believe the same rules about sourcing apply as well to ethnicity as to religion. And I'm all for people celebrating the accomplishments of their own ancestors but I find the idea of imposing an ethnicity on other people, especially by stereotypes of looks or names, rather repugnant. —David Eppstein (talk) 15:11, 20 June 2012 (UTC)
 * So you feel that we should only label the ethnicity (versus nationality or citizenship) of a person if they themselves apply the label, rather than using sourced information about their parents or other ancestors? I guess this is an important question toward the right of a person to define themselves to the world and opens up questions in a number of fields of study and thought. It does seem a fundamental problem for Wikipedia, which as you indicate would just go by reliable sources, but where there does seem to be some wiggle room in BLP articles. Thanks again for taking the time to respond. Obotlig ☣  interrogate 15:23, 20 June 2012 (UTC)

I'm sorry that I didn't see this before. I took your page and hundreds of others off my watchlist following a block.

Of course, having a concern about antisemitism and trying to remove antisemitism from articles was one of the charges in my RfC/U complaint.

I suppose that it's best just to ignore or delete such stuff.

Kiefer .Wolfowitz  21:32, 17 July 2012 (UTC)

Thanks
Mea Culpa! I jumped on the Dilworth's Theorem edit without thinking it through. Thanks for fixing my mistake. Bill Cherowitzo (talk) 17:41, 22 June 2012 (UTC)
 * No problem. —David Eppstein (talk) 17:48, 22 June 2012 (UTC)