User talk:David Eppstein/2016c

Generalized Traveling Salesman Problem

Hi David, I'm new to Wikipedia so I don't know the protocol. I edited some text within the Traveling Salesman Problem page a couple of months ago to correctly reflect the earlier publication of the GTSP variant transformation (my username is cnoonphd) and then you undid the changes. What do we need to do to have the article correctly reflect the contributions?

- thanks, Chuck Noon cnoon@utk.edu — Preceding unsigned comment added by Cnoonphd (talk • contribs) 12:49, 2 July 2016 (UTC)

Subsequence

You win.

Clearly, "subsequence" is the spelling you grew up with. You seem to think it belongs to some sacred category of being-a-word, and that "sub-sequence" is a revolting violation of that status. I don't really care; I just think when a word is used twice in the space of two lines, it ought to be spelled the same way. The inconsistency was there when I arrived. I suppose, if "subsequence" is actually more or less universal in math and IT circles, my hiccuping over its resemblance to the much more common "subsequent" or "subsequently" (the last of which is primed for the thorough reader, appearing earlier in the article) really is just the mark of a rube who isn't fluent in the jargon. I am rolling my eyes, but I'm also in earnest. Fair enough. But try to follow me here: even if "sub-sequence" offends your aesthetics, it is hardly un-clear in its me-aning. I just think it reads better for the phonetic reason I have given. I write "co-operate", too, but not because I'm too dumb to understand "cooperate".

I am sorry I did not write an edit summary which might have led you to simply correct both instances the first time instead of lecturing me; and I maybe should have had the tact to re-edit (...) the other "sub-sequence" to "subsequence" myself instead of re-applying (...) my original change; and I almost certainly shouldn't post this on your talk page, since it will probably sound more peevish and infuriating to you than it needs to; all the same, try to take it easy. I am not an idiot. I get that it's a word.

Regulov (talk) 11:05, 5 July 2016 (UTC)

But I fixed the inconsistency. So what's the problem? —David Eppstein (talk) 16:09, 5 July 2016 (UTC)

No problem, sweetie. Carry on. Regulov (talk) 04:49, 6 July 2016 (UTC)

Saw this

Over at the WT:N RfC, you said, "I found ten notable female mathematicians to add new articles on in the last week." Do you have them listed somewhere here on WP? Perhaps at WP:Women in red? I'd be interested in helping start some of these, so long as I had a collaborator who understands their field and would help keep things phrased accurately and such, as I am not a mathematician. Montanabw^(talk) 17:42, 6 July 2016 (UTC)

I meant that I had already started the articles. They are: Rebecca Goldin, Barbara Niethammer, Marie Farge, Yvette Amice, Zoé Chatzidakis, Sandrine Péché, Monique Laurent, Dominique Picard, Angelika Steger, Mileva Prvanović, and (later) Stefanie Petermichl, Wanda Szmielew, and Bozenna Pasik-Duncan. Assistance expanding any of these would be welcome, of course. I found most of them by searching the German and French Wikipedias for articles on female mathematicians with no English interwiki (using the convenient fact that French and German are gendered languages), and there are still at least as many more that can be found that way, but this list of prizes for women mathematicians also looks worth checking for missing articles. AWM/MAA Falconer Lecturer and Krieger–Nelson Prize also have a fair number of redlinks. —David Eppstein (talk) 17:51, 6 July 2016 (UTC)

That's good stuff. May be worth posting at Women in Red. It seems quite a bit more of a challenge to figure out the significance of similarly-situated awards for people in third world nations, and particularly where they are in the liberal arts or the "soft" sciences. The Pakistani AfD is one in particular where there has to be someone who can assess the impact of national-level awards. Montanabw^(talk) 21:50, 6 July 2016 (UTC)

David B. Massey

Hi, could you perhaps have a quick look at this to see whether it meets WP:PROF. It sounds like it should, but at the moment the stub doesn't really show it. Thanks! --Randykitty (talk) 08:34, 7 July 2016 (UTC)

Ok, I've updated the article with some better sources. I think the clearest claim to notability is through his journal editorship or reviews of his books; pure math is a very low-citation field, so the usual path through having many highly-cited publications doesn't work very well. —David Eppstein (talk) 18:02, 7 July 2016 (UTC)

Kac bio

would you agree that the anecdote involving the misreading of the word "rigger" probably doesn't belong? If meant to be humorous, it no longer is.--Jrm2007 (talk) 21:46, 7 July 2016 (UTC)

Well, I'm not convinced that it plays any essential role in the story of Mark Kac's life. But on the other hand, we should not whitewash the events and attitudes of people from the past to try to pretend that they had modern sensibilities about racism or other such topics, or that they took an equal level of offense at certain kinds of language as we would today. So if this anecdote is significant, the fact that it relies on offensive language and is now much less humorous than it might previously have seemed to be should not prevent us from including it, per WP:NOTCENSORED. —David Eppstein (talk) 21:51, 7 July 2016 (UTC)

There are probably any number of anecdotes in various people's lives that can be included or not. I believe that the set of anecdotes provided were meant to be humorous and this really isn't. Does Wikipedia have an article which lists jokes involving that word? If so, maybe this is okay. Anyway, not a big deal either way, I guess.--Jrm2007 (talk) 22:30, 7 July 2016 (UTC)

I think it does differ from the other anecdotes in that they all provide some insight into his research (or others' reactions to his research) while that one is just a misunderstanding of wording that doesn't end up saying much about Kac. So probably it can be removed on that basis. —David Eppstein (talk) 22:43, 7 July 2016 (UTC)

vector calculus article

i realize you did not contribute to the article but i am not comfortable enough with math from decades ago to know for sure whether it is inaccurate when it uses the term vector fields rather than the term vector in the algebra section: https://en.wikipedia.org/wiki/Vector_calculus

like dot product is two vectors not two vector fields, i think.--Jrm2007 (talk) 17:02, 8 July 2016 (UTC)

Request for reviews for my edits about combinatorial game theory

I went through Playing Games with Algorithms: Algorithmic Combinatorial Game Theory and updated all the pages for all the games surveyed in it, and also made some other updates related to it.

While it would be great if you could go through my edits in the past 3 days, a few items I particularly want you to review are these:

• Go and mathematics. I rewrote the Computational complexity section.
• Chess#Mathematics and computers. I reorganized the section and mentioned the main combinatorial game theory analyses on chess.
• Nondeterministic finite automaton with ε-moves merged into Nondeterministic finite automaton
• Generalized geography. I read the Schaefer (1978) paper and made vector diagrams from the paper, and put them in Generalized geography#Computational Complexity.

Also, do you think Erik Demaine's Constraint Logic warrants a Wikipedia page?

Cosmia Nebula (talk) 20:51, 11 July 2016 (UTC)

Why

.. does this article Extension:Graph/Demo/RawData:PopulationByCountryHistoric-csv still exist. Are you an administrator and able to move it to the author's draft space and get this page removed? Can I change the tag to speedy deletion? Some other editors might be confused about the 'speedy' part of the request. Best Regards, — Preceding unsigned comment added by Barbara (WVS) (talk • contribs)

Why are you asking me? It was Doc James' file, and it looks like he has now deleted it. I looked at it as a possible G6 speedy earlier but didn't because (1) it was prodded anyway, so there was no hurry to make sure something happened, and (2) Doc James wanted more time to figure out where else it should have been placed. —David Eppstein (talk) 16:02, 14 July 2016 (UTC)

The Conventioneers

Hey David, I noticed you deleted The Conventioneers page two years ago due to notability and sourcing concerns. I'd like to take a shot at making it. One of the episodes of the show caused a small controversy with the Canadian Broadcast Standards Council. The show also landed some international distribution in the US and Australia. Episode count-wise, the show ran for 7 seasons. Damnedfan1234 (talk) 12:25, 15 July 2016 (UTC)

It was just a WP:PROD, so if you want me to undelete it I can — just ask. —David Eppstein (talk) 16:19, 15 July 2016 (UTC)

Thanks for notice on edit war

Thanks for the notification, I was actually not aware of the "three revert" rule, but it does make sense. LaurentianShield (talk) 20:30, 16 July 2016 (UTC)

You're welcome. You were not over the limit, I think, but getting close, so better to be warned than to get in trouble. —David Eppstein (talk) 20:32, 16 July 2016 (UTC)

Paper Soccer

Hi, can you copyedit article Paper Soccer? I saw that you have edited Dots and boxes, mybe you would be interested in this article? Regards. Dawid2009 (talk) 20:50, 19 July 2016 (UTC)

my edit to Euclidean TSP

"..., , they're still numbers that obey the triangle inequality", but if that's all they need to be, then the decision version isn't obviously in NP. (See http://cs.smith.edu/~orourke/TOPP/P33.html and http://www.openproblemgarden.org/op/complexity_of_square_root_sum and http://math-www.uni-paderborn.de/agpb/work/submitted.july.pdf for evidence that the resulting problem isn't even known to be in the polynomial hierarchy.) The integer-distance and rational-distance version are equivalent under DLOGTIME-uniform TC0 many-one reductions (http://www.cse.iitk.ac.in/users/manindra/CS642/Division-Hesse.pdf) by clearing denominators, so that difference can only matter if we're considering classes which are not known to be closed under such reductions. On the other hand, if we want to allow _irrational_ numbers in the input, then which ones - Q-linear combinations of radicals? all algebraic numbers? elementary (https://en.wikipedia.org/wiki/Elementary_function) constants? I'm certainly not aware of any proof that those are equivalent under Turing reductions by (not contrived-to-achieve-the-goal) classes that aren't known to already decide the existential theory of the reals. In fact, is Euclidean TSP even known to become in NP when the coordinates are in unary? (https://duckduckgo.com/Unary_numeral_system?iax=1&ia=about) — Preceding unsigned comment added by JumpDiscont (talk • contribs) 09:19, 22 July 2016 (UTC)

If I don't see a response (to the "which ones", or otherwise) after another week, then I will re-do that edit. JumpDiscont (talk) 10:26, 30 July 2016 (UTC)

Is that a threat? The Euclidean TSP absolutely is a special case of the TSP as an abstract mathematical problem with real number distances, and your edit was flat wrong because of that. It is also true for trivial syntactic reasons that Eucldean instances are not special cases of metric ones: the Euclidean instances have coordinates as their input data and the metric ones have a distance matrix. It is also true for less trivial reasons that it's not easy to translate Euclidean instances into integer-metric instances, because of the square roots. Your edit falsely confuses all of those levels. —David Eppstein (talk) 16:12, 30 July 2016 (UTC)

(for your question: No - I expected you to still not respond, and wanted to have that as another thing to point to if you reverted again with no response here.) As "abstract mathematical problem"s, lots of claimed memberships of [non-number-theory problems with numbers in the input] in classes that don't end in "-hard" (for example, https://books.google.com/books?id=z4zMiZyAE1kC&pg=PA73&lpg=PA73&dq=maximum+flow+%22is+in+P%22 , http://people.csail.mit.edu/stefje/papers/subcutsShort.pdf , https://www.researchgate.net/publication/221462004_The_maximum_weight_perfect_matching_problem_for_complete_weighted_graphs_is_in_PC , http://www.cs.cmu.edu/~sandholm/nash_complexity.GEBBeforeLayoutEditors.pdf) are "flat wrong", since there's no way to represent the possible inputs with distinct elements of {0,1}*. I suppose I could nonetheless separate those levels, yielding

"When the input numbers can be arbitrary real numbers, Euclidean TSP is a particular case of metric TSP, since distances in a plane obey the triangle inequality. When the input numbers must be integers, Euclidean TSP is not even known to be in P^#P, since points with integer coordinates can have irrational distances.

Like the general TSP, Euclidean TSP is NP-hard in either case. With rational coordinates and discretized metric (distances rounded up to an integer), the problem is NP-complete.[21] With rational coordinates and the actual Euclidean metric, Euclidean TSP is known to be in the Counting Hierarchy[ref], a subclass of PSPACE. With arbitrary real coordinates, Euclidean TSP cannot be in such classes, since there are uncountably many possible inputs. However, in some respects Euclidean TSP seems to be easier ..."

, with [ref] pointing to http://epubs.siam.org/doi/abs/10.1137/070697926 and the ... starting with "than the general metric TSP. For example, the minimum spanning tree of the graph associated ...", as is currently the case. JumpDiscont (talk) 15:35, 3 August 2016 (UTC)

I find the MST evidence unconvincing, because you can solve the EMST without having to deal with sums of square roots. Better evidence is that the ETSP has a PTAS and the metric TSP doesn't. Also, re P^#P: I'm not actually sure of the complexity there. A lot of problems involving real number computation are actually lower down on the hierarchy. See e.g. existential theory of the reals. —David Eppstein (talk) 16:39, 3 August 2016 (UTC)

Good point regarding MSTs, I'll have to think about that more. Regarding "lower down in the hierarchy":

I am aware that quantifier elimination parameterized by number of variables is in XNC_unif (https://complexityzoo.uwaterloo.ca/Complexity_Zoo:X#xpuniform).

I have skimmed the articles on the Ellipsoid method and Karmarkar's algorithm, but cannot work out whether-or-not they need the feasible region to have non-empty interior.

I'm not aware of any results for more general linear programming (eg. constraints with < or ≠, or empty-interior instances if the above two don't handle that situation), though I suspect such results are known.

From the canonical form given at https://en.wikipedia.org/wiki/Linear_programming, when c's entries are square-roots of unary positive integers, rather than rational numbers, I'm not aware of any result which will put the resulting problems on a significantly lower level than posSLP (http://epubs.siam.org/doi/abs/10.1137/070697926), even when [[the origin is in the feasible region's interior] and one is given a positive integer B in unary such that [points on the feasible region's boundary all have norm greater than 1/B] and [one is promised (https://en.wikipedia.org/wiki/Promise_problem) that points in the feasible region all have norm less than B and there is a unique solution and that solution's coordinates are all positive integers]].

Is the "more general linear programming", or the promise problem described between that sentence and this sentence, or a generalization of one of those, an example of one of the "problems involving real number computation" you were talking about that's "actually lower down on the hierarchy"? If no, what are examples of such problems? JumpDiscont (talk) 03:02, 4 August 2016 (UTC)

Re "lower down in the hierarchy": the version of ETSP in which the points have integer coordinates is clearly in ${\mathsf {NP}}^{X}$ where $X$ is an oracle for comparing lengths of polygonal chains. We don't know what the complexity of that comparison problem is, exactly, but it's clearly in the existential theory of the reals because it's easy to set up an existential formula whose variables are the lengths of each segment and use it to express a constraint that one chain is longer than the other. Therefore, X is in $\exists \mathbb {R}$ and ETSP is in ${\mathsf {NP}}^{\exists \mathbb {R} }\subset {\mathsf {PSPACE}}$. As you say this isn't quite enough to put it into ${\mathsf {P}}^{\#{\mathsf {P}}}$. However, $\exists \mathbb {R}$ is generally considered more like ${\mathsf {NP}}$ than like ${\mathsf {PSPACE}}$ (the two more-conventional classes it's sandwiched between) and that's what I meant by lower in the hierarchy: not the polynomial hierarchy precisely but something analogous involving real number computation. Anyway I would be wary of putting anything about how ETSP relates to these complexity classes into the article without reliable sources that explicitly address this question. —David Eppstein (talk) 06:49, 5 August 2016 (UTC)

Well, the _decision version_ is in ${\mathsf {NP}}^{X}$. Unlike standard NPO (https://complexityzoo.uwaterloo.ca/Complexity_Zoo:N#npo) problems, when %2% is replaced with either "search-to-minimum_length" or "minimum_length-to-decision", I don't see any deterministic %2% reduction for ETSP, since there's no known good-enough lower bound on the differences between distinct outputs of the objective function. (I do see a _zero-error_ minimum_length-to-decision reduction, by iteratively choosing approximately-uniformly a tour whose length is strictly between the current lower bound and the current upper bound, until there are no such tours.) However, ETSP (integer or rational coordinates; DLOGTIME-uniform TC0 many-one reductions can convert the latter to the former) really is solvable by (UP ∩ coUP) $^{\exists \mathbb {R} [1]}$ (https://complexityzoo.uwaterloo.ca/Complexity_Zoo:P#pnpk), since $\exists \mathbb {R}$ can express that tour_length,tour is lexicographically least. I believe http://www-math.uni-paderborn.de/agpb//work/submitted.july.pdf is RS for membership in the Counting Hierarchy, so my current idea for the article is

"When the input numbers can be arbitrary real numbers, Euclidean TSP is a particular case of metric TSP, since distances in a plane obey the triangle inequality. When the input numbers must be integers, comparing lengths of tours involves comparing sums of square-roots.

Like the general TSP, Euclidean TSP is NP-hard in either case. With rational coordinates and discretized metric (distances rounded up to an integer), the problem is NP-complete.[21] With rational coordinates and the actual Euclidean metric, Euclidean TSP is known to be in the Counting Hierarchy[ref0], a subclass of PSPACE. With arbitrary real coordinates, Euclidean TSP cannot be in such classes, since there are uncountably many possible inputs. However, Euclidean TSP is probably the easiest version for approximation[ref1]. For example, the ..."

with [ref0] pointing to http://www-math.uni-paderborn.de/agpb//work/submitted.july.pdf (rather than SIAM, which I just discovered restricts access), [ref1] pointing to http://web.mit.edu/urban_or_book/www/book/chapter6/6.4.7.html, and the ... continuing "minimum spanning tree of the graph associated". JumpDiscont (talk) 19:10, 9 August 2016 (UTC)

I have looked at my previous comment's idea and the article again, and still have the same idea for an edit to the article. Do you have any comment on that proposed edit? JumpDiscont (talk) 12:30, 24 August 2016 (UTC)

I just put that into the article. JumpDiscont (talk) 01:16, 15 September 2016 (UTC)

DYK nomination of Aryness Joy Wickens

Hello! Your submission of Aryness Joy Wickens at the Did You Know nominations page has been reviewed, and some issues with it may need to be clarified. Please review the comment(s) underneath your nomination's entry and respond there as soon as possible. Thank you for contributing to Did You Know! MASEM (t) 16:44, 22 July 2016 (UTC)

DYK for Irene Barnes Taeuber

On 24 July 2016, Did you know was updated with a fact from the article Irene Barnes Taeuber, which you recently created, substantially expanded, or brought to good article status. The fact was ... that Irene Barnes Taeuber "helped found the science of demography"? The nomination discussion and review may be seen at Template:Did you know nominations/Irene Barnes Taeuber. You are welcome to check how many page hits the article got while on the front page (here's how, Irene Barnes Taeuber), and it may be added to the statistics page if the total is over 5,000. Finally, if you know of an interesting fact from another recently created article, then please feel free to suggest it on the Did you know talk page.

Cas Liber (talk · contribs) 02:32, 24 July 2016 (UTC)

Anna Estelle Glancy

Hi David.

Looking through the article history for Anna Estelle Glancy, I see it was accepted by Daniel Kenneth, however you decided it was a good idea to delete the whole article, leaving only has 1 opening line rather than the nearly 2000 word document I prepared, wrote and cited.

Can you please explain why you felt it was a good idea to delete my whole work when it had previously been accepted?

Thanks. — Preceding unsigned comment added by OpticalHistorian (talk • contribs) 00:50, 25 July 2016 (UTC)

Because whole paragraphs of it were copied from other sources. All text in Wikipedia must be in your own words, not copied from elsewhere. Someone else missing this problem earlier doesn't stop it from being a major problem. —David Eppstein (talk) 00:54, 25 July 2016 (UTC)

Thank you for that insight. Do you know which paragraphs were in question, so I can fix the issue rather than rewrite the article? — Preceding unsigned comment added by OpticalHistorian (talk • contribs) 01:36, 25 July 2016 (UTC)

You don't even know what you copied? And you want me to tell you? It's difficult for me to tell because parts that were clearly a copy-and-paste were later changed by other editors, disguising but not removing the problem. How about to atone for your sin you rewrite all of it. I left all the sources in place. But don't copy any text, and also don't just change a few words but keep the same thoughts in the same order – that's close paraphrasing and it's still unacceptable. Didn't they teach you these things in school? —David Eppstein (talk) 03:37, 25 July 2016 (UTC)

OK then. Based on your tone and quite frankly personal attack on myself, I can see that you get plagiarism issues quite frequently. So I will forgive you here, but what you have failed to realize is that the very nature of me trying to contact you for assistance must highlight that I genuinely had no idea the article had been copied in places. You see, a colleague had written and submitted the original article, to which they were told, contained "peacock terms" and therefore needed revision. After another attempt and the same circumstance, I was handed the task and set about reading through the article in the attempt to remove such peacock terms - not attempting to fix any plagiarism as according to various editors, this was no issue with this.

This team member has moved into a new role since, however I spent quite some time on attempting to re-write and fix the problem areas and therefore I am sure you can appreciate how disappointing it must be to have it finally accepted, but then swiftly deleted.

As this is the first I have heard of plagiarism being present, and given that it was a well respected team member who had written the article, I simply found it hard to believe that there were these issues present, hence why I asked for which paragraphs were apparently plagiarized. I hope this clears up any misunderstandings and I trust you can offer me some insightful advice in moving forward, rather than simply "rewrite it".

So like I mentioned in my earlier comment, I do appreciate your insight into this topic, however I don't see why it is necessary to begin an attack on me and my apparent sin of merely trying to upload an article, so the public can appreciate what this incredible woman has brought to the world of Optics.

Thank you in advance for your assistance. — Preceding unsigned comment added by OpticalHistorian (talk • contribs) 08:20, 25 July 2016 (UTC)

DYK for Aryness Joy Wickens

On 26 July 2016, Did you know was updated with a fact from the article Aryness Joy Wickens, which you recently created, substantially expanded, or brought to good article status. The fact was ... that as acting commissioner of the Bureau of Labor Statistics, Aryness Joy Wickens was the highest-paid woman in the US civil service in 1954? The nomination discussion and review may be seen at Template:Did you know nominations/Aryness Joy Wickens. You are welcome to check how many page hits the article got while on the front page (here's how, Aryness Joy Wickens), and it may be added to the statistics page if the total is over 5,000. Finally, if you know of an interesting fact from another recently created article, then please feel free to suggest it on the Did you know talk page.

Cas Liber (talk · contribs) 01:32, 26 July 2016 (UTC)

174.3.155.181

Re:admonishment not to do that again, 174.3.155.181 did it again. Fountains of Bryn Mawr (talk) 02:41, 26 July 2016 (UTC)

Thanks for the heads up. —David Eppstein (talk) 03:40, 26 July 2016 (UTC)

So, User:Gagz7 suddenly came to life backing 174.3.155.181 editsdiff using 174.3.155.181 arguments and even 174.3.155.181 talk formattingdiff, and taking up 174.3.155.181 causes at another articlediffdiff. Also did 174.3.155.181's bidding herediffdiff, followed on by another reverting IPdiff. If I am being a dim Captain Obvious tell me to go away to ANI and SPI. Fountains of Bryn Mawr (talk) 14:48, 26 July 2016 (UTC)

so, have you provided any evidence for your assertions made against IP, in light of the new evidence that never entered, nor requires, RfC? i would love to hear your arguments about how the two new sources, both using Gregory's own words, are insufficient. please do share User:Fountains of Bryn Mawr. you doth protest too much, whilst providing very little, i may add. thanks Gagz7 (talk) 14:53, 26 July 2016 (UTC)

typical of User:Fountains of Bryn Mawr to go ahead and revert without answering my question about what the new sources are lacking, especially since they are in the "influencer"'s own words. looking at their own contributions to this conversation, i cannot say i am surprised with their behaviour. it seems they feel entitled to make edits without any expertise, or in absence of evidence, fact, or reason.

• may i ask what your contributions have added to this site, User:Fountains of Bryn Mawr? comparing Special:Contributions/174.3.155.181's brief 8 month edit history to your ten year career, i can say with great confidence that the content of their additions and contributions have already surpassed yours. it is not easy to find experts in difficult areas of mathematics who generously donate their time to improve understanding of complex concepts such as content (measure theory), or Dual norm, or Isometry, etc.

it seems you do not respect the editor's expertise in mathematics, but wikipedia is in great need of good editors in this difficult subject area. i cannot see how you can expect your opposition to stand when IP went out of his way after noticing the closed (indeterminate) RfC, to spend even more time to produce inarguably the two strongest sources for Gregory's influence on Barrow, using the Gregory's own words. such language employed by gregory is rarely employed, unless his influence was substantial.

it seems IP, and now myself, are adamant about this edit due to the belief "standing on the shoulders of giants", which is a mindset that pervades mathematics and was arguably instilled by the great Isaac Newton, who was indirectly influenced by Gregory as well (Barrow was inarguably the primary one, though) Gagz7 (talk) 15:55, 26 July 2016 (UTC)

Fountain pen article review

Hi David, thank you your comments on the fountain pen FA and GA nominations. Upon noticing the article was at FA level in the past, I attempted to fix the issues raised during demotion to bring the article back up to FA status.

I now understand that I prematurely nominated the article for FA and GA, and will focus on making edits which rectify the issues in the GA submission first. I will also re-familiarise myself with the appropriate criteria regarding references. Thanks again for your help! Seba5tien (^talk/_contribs) 04:58, 26 July 2016 (UTC)

Please do also review all of the GA criteria, not just the ones I noticed on a quick read-through, because there is likely a lot more that I missed and it will simplify things to do it sooner rather than later. —David Eppstein (talk) 05:18, 26 July 2016 (UTC)

I've worked through the article making edits where appropriate. I think it now meets the GA criteria, but would especially appreciate additional clarification about whether the article meets criteria point 2 (verifiable). Thanks! Seba5tien (^talk/_contribs) —Preceding undated comment added 07:21, 26 July 2016 (UTC)

I've Pinged You

I realize that I pinged you already for a discussion at WP:ANI about User:Gagz7 and User:174.3.155.181. Since you were the blocking admin for the latter, would you mind weighing in at the discussion? -- Gestrid (talk) 16:41, 26 July 2016 (UTC)

DYK nomination of Margaret Jarman Hagood

Hello! Your submission of Margaret Jarman Hagood at the Did You Know nominations page has been reviewed, and some issues with it may need to be clarified. Please review the comment(s) underneath your nomination's entry and respond there as soon as possible. Thank you for contributing to Did You Know! Yoninah (talk) 20:34, 26 July 2016 (UTC)

I have unreviewed a page you curated

Hi, I'm Slashme. I wanted to let you know that I saw the page you reviewed, Amanda Swart, and have un-reviewed it again. If you have any questions, please ask them on my talk page. Thank you. Slashme (talk) 21:24, 26 July 2016 (UTC)

@Slashme: I did not curate that page. It may have been listed as auto-curated when I created it? —David Eppstein (talk) 21:51, 26 July 2016 (UTC)

Indeed, and I didn't put this message on your talk page, it was automatically done when I uncurated the article. Because the timing of the article's creation was so close to my comments at Wikipedia:Articles_for_deletion/Webe_Kadima, I figured that you might have created the article in response to a comment that I made, and I have a CoI, so I thought it wise to put the page back into the new pages feed. --Slashme (talk) 21:55, 26 July 2016 (UTC)

DYK for Margaret Jarman Hagood

On 29 July 2016, Did you know was updated with a fact from the article Margaret Jarman Hagood, which you recently created, substantially expanded, or brought to good article status. The fact was ... that Margaret Jarman Hagood, a sociologist who wrote a book on Mothers of the South, became a mother herself before completing her bachelor's degree? The nomination discussion and review may be seen at Template:Did you know nominations/Margaret Jarman Hagood. You are welcome to check how many page hits the article got while on the front page (here's how, Margaret Jarman Hagood), and it may be added to the statistics page if the total is over 5,000. Finally, if you know of an interesting fact from another recently created article, then please feel free to suggest it on the Did you know talk page.

Cas Liber (talk · contribs) 12:02, 29 July 2016 (UTC)

DYK for Kate Claghorn

On 30 July 2016, Did you know was updated with a fact from the article Kate Claghorn, which you recently created, substantially expanded, or brought to good article status. The fact was ... that a 1923 book by Progressive Era activist Kate Claghorn has been called "the one significant contemporary study of the immigrant and the American legal system"? The nomination discussion and review may be seen at Template:Did you know nominations/Kate Claghorn. You are welcome to check how many page hits the article got while on the front page (here's how, Kate Claghorn), and it may be added to the statistics page if the total is over 5,000. Finally, if you know of an interesting fact from another recently created article, then please feel free to suggest it on the Did you know talk page.

Cas Liber (talk · contribs) 00:01, 30 July 2016 (UTC)

INFORMS links

Before I continue removing links, there seems to be an effort to add INFORMS links to various articles [1]. There are several IPs adding the links in and it looks very spammy. However, I defer to you. Should these continue to be removed or shall I revert the ones I removed already? -- Gogo Dodo (talk) 06:57, 31 July 2016 (UTC)

The fact that Special:LinkSearch finds many links to INFORMS is completely unsurprising. It is a serious and well-established academic organization, the primary professional society of operations researchers, publisher of major academic journals on that subject, etc. Removing its links indiscriminately would be a disaster. —David Eppstein (talk) 07:02, 31 July 2016 (UTC)

Sorry, I didn't mean to infer to delete all of them. Just the ones that have been added in a spammy manner by these IPs:

• 128.84.124.186 (talk · contribs · WHOIS)
• 67.241.75.68 (talk · contribs · WHOIS)
• Aea68 (talk · contribs)
• 2604:6000:b441:dc00:60dc:1890:7d36:3dfa (talk · contribs · WHOIS)
• 2604:6000:b441:dc00:493c:cb77:6dfb:e5c9 (talk · contribs · WHOIS)

I think there might be a few more. It seems like someone is going through https://www.informs.org/About-INFORMS/History-and-Traditions/Biographical-Profiles and adding links to everyone who has a Wikipedia page. If I'm wrong though, I have no problem reverting all my edits. -- Gogo Dodo (talk) 07:14, 31 July 2016 (UTC)

And the subpages of https://www.informs.org/About-INFORMS/History-and-Traditions/OR-Methodologies, which is really just a list of links to their biography articles, so I'm not sure that is such a good external link? -- Gogo Dodo (talk) 07:18, 31 July 2016 (UTC)

The biographic profiles look ok as external links (or even references) on our corresponding bios but if the OR-Methodologies links really are only links to related bios then I think they should go. —David Eppstein (talk) 07:33, 31 July 2016 (UTC)

Alright, I will revert my removal of the biography links. The OR-Methodologies are just a list of links to their biographies with some external links to publications. Like the Game theory one https://www.informs.org/About-INFORMS/History-and-Traditions/OR-Methodologies/Game-theory -- Gogo Dodo (talk) 07:40, 31 July 2016 (UTC)

Deletion review

I am notifying everyone who took part in the AFD discussion on Daniel Romanovsky. Wikipedia:Deletion review/Log/2016 August 3 Thoughtmonkey (talk) 18:58, 3 August 2016 (UTC)

Bloom filters in binary search algorithm

Please take a look at my comment in Talk:Binary search algorithm, and reply if you disagree. --Macrakis (talk) 14:06, 4 August 2016 (UTC)

AfD: Nominated for deletion; see Wikipedia:Articles for deletion/Miranda Cheng

A discussion is taking place as to whether the article Miranda Cheng is suitable for inclusion in Wikipedia according to Wikipedia's policies and guidelines or whether it should be deleted.

The article will be discussed at Wikipedia:Articles for deletion/Miranda Cheng until a consensus is reached, and anyone is welcome to contribute to the discussion. The nomination will explain the policies and guidelines which are of concern. The discussion focuses on high-quality evidence and our policies and guidelines.

Users may edit the article during the discussion, including to improve the article to address concerns raised in the discussion. However, do not remove the article-for-deletion notice from the top of the article. Merrybrit (talk) 03:47, 6 August 2016 (UTC)

Reverted edit about Fisher-Yates

Hi David,

I noticed that you reverted (diff) an edit I made to the Fisher-Yates shuffle article. In my edit, I deleted a claim that I thought was false. I'd like to double-check with you.

The claim was that repeating two-way random events can only produce distributions where probabilities have denominators that are powers of two. We can create a counter-example by flipping a pair of coins as follows:

HH -> 0
HT -> 1
TH -> 2
TT -> flip again

Here, we've created events with 1/3 probability by using a source with two-way random events.

Let me know if this seems right. Thanks!

--Ngy25 (talk) 07:11, 7 August 2016 (UTC)

The phrase "repeated a bounded number of times" is important. Your "flip again" causes the number of repetitions to not be bounded. —David Eppstein (talk) 07:43, 7 August 2016 (UTC)

Information Request

I would be grateful if you could provide me a specific academic article for reading. It's details : Rosengarten, D (2002). "Y Chromosome Haplotypes among Members of the Caucasus Jewish Communities". Ancient Biomolecules. Hebrew Mountain Man (talk) 17:39, 12 August 2016 (UTC)

The only volume of that journal that I can see online (at http://www.tandfonline.com/loi/ganb20) is Volume 4, but that's the volume for 2002. It lists nothing by Rosengarten and nothing by that title. Google scholar also doesn't know about this paper. An online reference I found at https://www.tib.eu/en/search/id/BLCP%3ACN045257058/Y-Chromosome-Haplotypes-Among-Members-of-the-Caucasus/ suggests that it might be in vol.4 issue.3, p. 152 but the journal's page for that issue doesn't list anything that would match. The same online reference also suggests that it can be found in an Israeli conference proceedings, with no indication whether it is online. Do you have anything more to go on? Rosengarten has other papers on related topics that are more accessible. Or you could try emailing him — see http://www2.tau.ac.il/Person/medicine/researcher.asp?id=adkhkjccf for contact information. —David Eppstein (talk) 22:18, 15 August 2016 (UTC)

Hello and thank you. I search for information about genetic studies on mountain Jews (specifically on this group). As far as I know, there were two scientific works on the subject: one focused on mtdna and the other on Y haplogroups. Do you know about other works on the subject? Hebrew Mountain Man (talk) 22:37, 15 August 2016 (UTC)

Searching Google scholar for "genetics" "caucasian jews" finds ~50 papers (some probably listed only because they cited a different study with that phrase in the title). —David Eppstein (talk) 23:22, 15 August 2016 (UTC)

I couldn't find even one paper that includes Y-haplogroup results of mountain Jews. Could you? Hebrew Mountain Man (talk) 00:04, 16 August 2016 (UTC)

Did you look at "Localizing Ashkenazic Jews to Primeval Villages in the Ancient Iranian Lands of Ashkenaz", Das et al., Genome Biology and Evolution 8 (4): 1132-1149? —David Eppstein (talk) 00:52, 16 August 2016 (UTC)

Thank you. I have read the papers that you have suggested (the mentioned one and those related to it) but none of them show Y-haplogroup results of mountain Jews. I am searching for something like this (only this paper focuses on mtdna) "Counting the Founders: The Matrilineal Genetic Ancestry of the Jewish Diaspora" see results at table s4. You can see that 58.62% of mountain jews belong to J2b1 mtdna. If you can find something like this about Y-haplogroup it will be much appreciated. Hebrew Mountain Man (talk) 10:51, 16 August 2016 (UTC)

I'm not a genetics researcher, nor particularly interested in this topic per se. Why me? I thought you were contacting me because I might have easier institutional subscription access to a journal. But if what you need is someone to help you search, the people trained and paid to do that are called librarians. You could try asking one of them. —David Eppstein (talk) 16:16, 16 August 2016 (UTC)

Ok, thank you. I just want to know one more thing - can I have access to Jstor? I know that some wikipedians can get such access. Can you as an administrator give me the permission needed to use Jstor, with unlimited access to academic papers? Hebrew Mountain Man (talk) 17:46, 16 August 2016 (UTC)

I can't get you direct or unlimited access to jstor. I do have access myself (through my employer, not through Wikipedia) so I can email you copied of individual articles on jstor if you give me the url. —David Eppstein (talk) 17:52, 16 August 2016 (UTC)

Ok. Hebrew Mountain Man (talk) 17:58, 16 August 2016 (UTC)

California State Legislature resolution and Academic Decathlon resolution

I tried to find an article to use File:CA Leg Res 234 1981.jpg in, but it felt too marginal for any of California State Legislature, United States Academic Decathlon and Palo Alto High School. Pity. Maybe the signatures could be cropped and used in David Roberti, Mike Curb, Lou Papan and Willie Brown (politician)? We also have Byron Sher. But no article for Marz Garcia. Carcharoth (talk) 16:24, 17 August 2016 (UTC)

Thanks for trying. If you do feel a crop would be useful somewhere, go ahead. —David Eppstein (talk) 17:09, 17 August 2016 (UTC)

Hypercube

I assume it's wrong to describe a point as a "shape" as well? I wrote that sentence wholesale, earlier today, to fill an awkward gap where the section just starts by saying "zero!" with no context - I probably wrote it quite badly, by all means replace it with something more coherent. --McGeddon (talk) 15:56, 22 August 2016 (UTC)

I don't see why a point can't be called a shape. —David Eppstein (talk) 17:41, 22 August 2016 (UTC)

Addressing the revert on my edit to the anti-aliasing page.

How did I misinterpret the how-to? I saw the words must and should, those are advice words. I don't know what most widely accepted means so I got rid of it because it is a weasel word or non-precise word. See WP:W2W. Please compare my revisions. Improve suggests that Wikipedia thinks it makes something better. Wikipedia shouldn't assume that things are either being improved or worsened. That is not neutral.

That may inspire me to add to my essay on how to write or edit Wikipedia articles.

— Preceding unsigned comment added by Turkeybutt JC (talk • contribs) 18:55, 25 August 2016 (UTC)

 Thanks SineBot. --Turkeybutt (talk) 23:20, 26 August 2016 (UTC)

In my experience, WP:NOTHOWTO is good advice when applied to articles about kinds of foods (we should not include explicit recipes) or about video games (we should not give how-to-play guides) but very bad advice in articles about algorithms, because the entire point of an algorithm is that it's a formalization of how to do something, and we can't describe the algorithm without saying how to do it. Material that explains how something works or how people do a certain thing is not a violation of WP:NOTHOWTO. It is not even a violation when it describes why doing things one way might be better than doing it a different way, as long as that is sourced. And it is also not a violation when an algorithm is described step-by-step, in pseudocode. See the wording in WP:NOTHOWTO: "Describing to the reader how people or things use or do something is encyclopedic". That kind of description is what anti-aliasing contains, and so it is not problematic.

As for your suggestion that using the term "improve" is non-neutral: the world is non-neutral, and we are here to describe the world. We can't do so by pretending everything is equal to everything else, and that's not what WP:NPOV tells us to do. Rather, what we need to do to follow WP:NPOV is to be careful that, when we include an evaluation saying that something is better than something else, we are doing so on the basis of reliable sources rather than our own opinions. —David Eppstein (talk) 23:17, 25 August 2016 (UTC)

But how do we know if a source is reliable? Wikipedia wants to be a tertiary source. If reliable sources says "Adolf Hitler was a bad man", that doesn't mean we can just say this:

• Adolf Hitler was a bad man. ^[1] because he conducted the Holocaust that killed up to about 13 million people. That's not neutral.
• According to reliable sources, Adolf Hitler was a bad man. ^[1] That is because he conducted the Holocaust that killed up to about 13 million people. Saying according to reliable sources sounds awkward, unless you actually list what the reliable sources are.

There are correct ways to write that.

• Adolf Hitler conducted the Holocaust that massacred up to about 13 million people during his position as chancellor of Germany. [reliable source] states that he is a "bad man".^[1]
• Adolf Hitler conducted the Holocaust that massacred up to about 13 million people during his position as chancellor of Germany. He is a "bad man" according to [reliable source].^[1]

Reliable sources are written by human writers, and sometimes those writers' opinions can infect such sources, which means if it is considered reliable; the opinion virus can spread to Wikipedia. Blogs are not reliable sources. Tutorial videos aren't reliable sources either. Wikipedia is to answer what it is, not how to do it. That's why there's a Wikiversity.

Listing ways people do things is okay for Wikipedia, but telling people how to do them is not. Wikipedia articles shouldn't be training people.

The definition of neutral on Wikipedia confuses me. If the majority isn't neutral, but Wikipedia believes that NPOV means the point of view of the majority, then Wikipedia is subject to forced bias if the majority shares specific opinions or points of view, then Wikipedia won't be able to meet reliability standards. If experts or scholars say that God doesn't exist and many universities and reliable sources say that God doesn't exist, and almost everyone agrees that God doesn't exist, that shouldn't mean that Wikipedia articles should say that God doesn't exist either. That wouldn't be neutral. So I think Wikipedia has a flawed definition of neutral. There's even a template to tell readers and editors if an article is too human-centric.

Improve is subjective. Trump supporters and Islamophobes might think that Trump's bans on Muslims entering the US is an improvement to the country. But Muslims themselves and some people who have Muslim loved ones trying to enter the United States would disagree.

--Turkeybutt (talk) 23:13, 26 August 2016 (UTC)

Your idea that we should reject mentioning any subjective opinion is just wrong. We can and should include such opinions, attributed to sources, when they are held as the consensus of mainstream opinion, or in some cases when they are the opinion of a significant minority. More, in technical subjects such as anti-aliasing, comparisons (this algorithm is better than this other one) do not even have to be subjective: the quality of the two algorithms can be measured objectively (mathematically, or by running the algorithms and computing measures of the quality of their outputs, or by running experiments with humans to determine which output is preferable. There is no Wikipedia rule, and should be no rule, telling us not to report those results. —David Eppstein (talk) 00:03, 27 August 2016 (UTC)

List of computer science conferences

Hi, you reverted my addition of the IWANN conference: https://en.wikipedia.org/w/index.php?title=List_of_computer_science_conferences&type=revision&diff=729653202&oldid=729610154 May I know why? Matencia29 (talk) 21:29, 29 August 2016 (UTC)

Because all entries in that list need reliable published sources that are independent of the subject and attest to its significance. You only listed the conference web site, which is not independent of the subject. —David Eppstein (talk) 21:33, 29 August 2016 (UTC)

Most conferences would hardly pass this test, since neither Citeseer nor Arnetminer seem to be accesible. I have only been able to check MSAS. Maybe the reference to ERA should be replaced by CORE http://portal.core.edu.au/conf-ranks/ ? Matencia29 (talk) 22:40, 29 August 2016 (UTC)

Question of categories removed

Hi David. You removed my question about categories from the talk page of WP:Women scientists. Where can I pose this question? I am currently writing an article for a Springer volume in the Association for Women in Math series on writing women in mathematics into Wikipedia. I noticed that some women have the tag Category:Women mathematicians removed from their pages and instead the tag Category:American women mathematicians is inserted. From other discussions I think both tags are appropriate. I have written a pair of biographies and edited many more but I still don't know the nuances of Wikipedia culture. Thanks for any help you may provide and thanks too for your many articles on women in math. Mvitulli (talk) 16:21, 31 August 2016 (UTC)

I didn't remove it, I just moved it to the bottom of the talk page where new discussions are supposed to go, and left an answer there. —David Eppstein (talk) 17:22, 31 August 2016 (UTC)

Disambiguation link notification for September 1

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Nested relational model listed at Redirects for discussion

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Graphs in topology and lemma separation

To add a comment to this section, go to User:Mathmensch/Disc1wDE

Hello,

the lemma Graph (topology) has been transformed to a redirect to Topological graph theory, although it seems as though a graph in topology is merely the object of study of the latter. I am confused on when to construct new lemmata; certainly Linear Algebra and Vector space are two different articles, and even Group (mathematics) and Group theory (although this I find perhaps not right since group theory is only about groups, whereas linear algebra also studies matrices and so on, which is why one could argue for a merger between the two).

See also Wikipedia:Merging#Reasons_for_merger at "Merging should be avoided if:" 2. I assume the reason for the merger was 2. in the first list; I don't know whether context is required there; when reading Hatcher's book, this concept was presented to me without this particular context, and it was understandable.

Namely, I am currently reading Hatcher's book, and there are a couple theorems on graphs, like for instance that every graph contains a maximal tree, from that one can compute the fundamental group, covering spaces of graphs are again graphs, and there is also an application to group theory (subgroups of free groups are again free).

I would be particularly pleased if apart from the rules, which seem ambiguous here, I would gain knowledge on the day-to-day practice of merging lemmata and articles, so that I will be able to avoid creating new lemmata in vain by checking some more-or-less well-defined criteria on when not to do so.

Since you mentioned the possibility at the top of your talk page, I would invite you to reply at my own talk page, so that I am notified (furthermore my talk page is much less busy, and since your reply may shed some light on the issue, I may want to come back to it in the future, which is easier when the archive is somewhat less crowded). --Mathmensch (talk) 06:01, 5 September 2016 (UTC)

It's a fuzzy boundary, but to me the topics are similar enough that a new article would need to demonstrate the need for a new article by providing significantly more content about whatever it is about. In the case of Graph (topology), on the other hand, the new article was significantly shorter than the paragraph about the same topic within topological graph theory. —David Eppstein (talk) 06:12, 5 September 2016 (UTC)

Hello there,

1) May I move this section to my talk page?

2) If, say, I were to expand Graph (topology) so that it would contain significantly more content on the subject than topological graph theory, would you then think it is better to have two lemmas? --Mathmensch (talk) 12:37, 5 September 2016 (UTC)

I'd rather keep a copy here for my records, but if you want to copy it to your talk page I have no problem with that. I'm not sure why you call them lemmas; they're generally called articles here. But I'd have to see the expansion before formulating an opinion on it. —David Eppstein (talk) 20:10, 9 September 2016 (UTC)

I created a page (User:Mathmensch/Disc1wDE) which can be embedded in both our talk pages as a template. --Mathmensch (talk) 06:46, 10 September 2016 (UTC)

I just created a draft of Graph (topology) in my user namespace. I would ask for comment; it would be best if you could use the page User:Mathmensch/Disc1wDE for commenting, since this is embedded in both our talk pages. --Mathmensch (talk) 10:59, 10 September 2016 (UTC)

Ok, some comments:

• I think it's too WP:TECHNICAL. Here's my attempt at a more accessible start: "A topological graph is a topological space defined from an undirected graph by replacing each vertex by a point and each edge by a curve." You can see, I hope, that not requiring readers to already understand CW complexes and "the usual way" lowers the amount of background needed to understand this material. The same goes for all the rest of the material. You need to pay much more attention to whether the jargon and notation you are introducing is really necessary, or whether it is just there to make things look more mathy.
• In the same vein of reducing technicality, If you are going to discuss complexes, what is the point of using CW complexes? These are all just simplicial complexes, the added generality of CW complexes is pointless here.
• In general, many concepts that are used here are neither linked to pages describing them nor explained within the article, leaving the article readable only to people who are already familiar with those concepts. These include graphs (the normal kind of graph), skeleton, quotient topology, quotient map, gluing, closed, one-dimensional, unit ball, etc., and that's just in the lead section. The rest is if anything worse.
• In the bullet about "usual category of graphs", graphs points to a disambiguation page, and there is no actual link to the category of graphs. Also I thought the usual category of graphs was over directed graphs (and directed graph homomorphisms) but here the graphs are undirected.
• "The usual category of graphs and graph homomorphisms is naturally contained within the category of graphs" reads like a tautology. I think that the second instance of "category of graphs" should be replaced by something more like "category of topological graphs and continuous maps". Also, there is no entry for inclusion in Glossary of category theory so although I can guess I am a bit unsure what the right meaning of an inclusion of categories is supposed to be, especially in this case because it's not clear what the objects are — do two isomorphic combinatorial graphs lead to a single object in the category, or two different objects? What about two different but homeomorphic embedded topological graphs? And if they do all lead to different objects, which of multiple homeomorphic topological graphs is the one that is supposed to represent a given combinatorial graph?
• The applications section is missing a link to the main article Nielsen–Schreier theorem on this application.
• There are some closely related concepts that should be included,
• Are you assuming that the starting combinatorial graph is finite? Because otherwise the existence of a maximal tree would seem to need the axiom of choice or some similar assumption.
• It is not really even true that a topological graph is just a topological space of this form, right? Because the vertices are distinguished as special points of the graph. If you subdivide an edge of a graph, you get a different graph with the same topological space. So it is also not formally correct to toss around concepts like covering space, fundamental group, homotopy equivalence, etc., as if they applied to graphs. What they actually apply to is the underlying topological space, forgetting the distinction of some points as vertices.

—David Eppstein (talk) 21:21, 20 September 2016 (UTC)

Yes, these are all true. Gonna include them ASAP.

Could you give some info or a reference on the closely related concepts that are to be included? --Mathmensch (talk) 06:01, 21 September 2016 (UTC)

Although Hatcher's book defines them without point distinction. Let's see what we do here. --Mathmensch (talk) 06:05, 21 September 2016 (UTC)

Aha, perhaps the points are distinguished by being the 0-skeleton. This would mean that CW complexes have a "memory" for how they were formed, or the associated topological space does not bear all the information about CW complexes. Interesting. --Mathmensch (talk) 06:08, 21 September 2016 (UTC)

Some more thoughts:

• You really should be using more than one source.
• This does not line up well with graph homomorphisms because its continuous functions allow both edge subdivisions and edge contractions while graph homomorphisms don't.
• There's another kind of topological space derived from graphs (I think this idea is from Thurston but I don't have a source): make a non-Hausdorff space with a closed point for each vertex, an open point for each edge, and the closure of each edge being the set of it and its endpoints. For this one it actually is true that homeomorphism of spaces is the same as isomorphism of graphs, and it has much of the other properties you would want. Its continuous maps are almost like graph homomorphisms — no edge subdivision are possible — but homomorphisms after you augment the graph to have a self-loop on each vertex. So its categorical product becomes the strong product of graphs, etc.

—David Eppstein (talk) 18:44, 23 September 2016 (UTC)

Hmm, so there is a different structure (which seems still a fairly discrete one). As usual I agree on what has been said, and I will also look for more sources ASAP (for now I'm "a bit" busy). --Mathmensch (talk) 17:10, 25 September 2016 (UTC)

@David Eppstein: The article User:Mathmensch/sandbox/Graph_(topology) has now been submitted to be reviewed, after all your concerns were addressed. --Mathmensch (talk) 10:22, 1 February 2017 (UTC)

Thank you and appology

Hello. Wanted to take a moment to both thank and apologies. First, my apologies for the drive-by nominations. Your analysis of those was, I believe, accurate. I didn't take the necessary time that should have been taken before nominating them. I appreciated the feedback you left after those cases and I tried to carry it forward and learn from the lesson before nominating the Freeway Complex Fire. I obviously still missed some stuff and appreciate you helping me learn. The thank you is for the feedback and criticism you did give. I take it to heart and really appreciate the feedback on specific issues to address. I have just recently started trying to improve certain articles to GA status and so any insight and feedback I get is greatly appreciate. Thanks for the work you do! Hoping you are well, --Zackmann08 (^{Talk to me}/_{What I been doing}) 07:12, 5 September 2016 (UTC)

You're welcome, and thanks to you for taking these setbacks so constructively. —David Eppstein (talk) 07:15, 5 September 2016 (UTC)

I figure I can either take them as personal attacks and get all grumpy, or I can take them as constructive criticism and strive to learn from them. --Zackmann08 (^{Talk to me}/_{What I been doing}) 08:00, 5 September 2016 (UTC)

I wanted to see if I could get your gut reaction to Cedar Fire (2003). I've spent a few hours rewriting it and gave a good look at WP:GACR. It looks to be in pretty good standing at this point, my one concern is about the list of fatalities. It seems appropriate to have in the article but I'm not sure... Thoughts? --Zackmann08 (^{Talk to me}/_{What I been doing}) 23:02, 5 September 2016 (UTC)

I think your recent edits replacing the list of names and places by a shorter summary of the deaths is an improvement. —David Eppstein (talk) 20:11, 15 September 2016 (UTC)

Reliable sources

There seem to be at least a couple reliable sources regarding Guarantee Security Life Insurance Company, including this book and this article. Also this article. Concerned user (talk) 19:44, 9 September 2016 (UTC)

It was only deleted via WP:PROD, so if you want it back all you have to do is ask, either here or at WP:REFUND. —David Eppstein (talk) 19:59, 9 September 2016 (UTC)

Semi-protected edit request for the Pythagorean theorem

Hi David, sorry for not following proper protocol, the information box on my request says "set the |answered= or |ans= parameter to no to reactivate your request", so I thought I was doing the right thing. I've been talking to DVdm, though, and he or she has helping me with protocol. — Preceding unsigned comment added by Jgdowty (talk • contribs) 00:25, 12 September 2016 (UTC)

Lubomyr Luciuk

Mr Eppstein: I have no idea of who you are nor any understanding of why you seem to have an interest in deleting portions of the Wikipedia entry on me that includes basic information, most of which is a matter of public record. Who gave you editorial control over a biographical entry that I put on Wikipedia and that I have tried to keep up to date? Your editing seems intent on removing details about my career and activities. I would be grateful if you stopped revising the entry or, if you are somehow connected with Wikipedia, just delete it entirely rather than monkeying about with it. There is nothing controversial about any of it, and all of it can be substantiated by a simple Goggle search. I am not particularly interested in adding references to justify every revision I have made because my time is actually rather taken up with more important things. My entry is accurate (if far from complete) and that is all that it needs to be for the basic purposes of Wikipedia. That some nut job tried to insert polemical remarks a few years ago is indeed unfortunate but that matter was resolved (he has since been banned from several Canadian websites because of his apparent instability). So, please remove the header about the entry being contested and leave my entry as I have written it (and attempted to update it from time to time) or remove it entirely. Thanks.

Dr L Luciuk — Preceding unsigned comment added by 67.193.142.54 (talk) 21:09, 12 September 2016 (UTC)

You should not be editing the article here about yourself; see WP:AUTOBIO. Additionally, all claims in an article here, especially one about a living person, must be backed by reliable and verifiable sources (usually meaning something that has been published by a publisher independent of the subject). The material I remove violated this requirement and should not be added back without a source. —David Eppstein (talk) 21:23, 12 September 2016 (UTC)

• How is this guy even notable? EEng 08:03, 18 September 2016 (UTC)

Lyapunov functions

Since you, too, removed Myrocarcassonne's contributions (from List of unsolved problems in mathematics), would you mind weighing in here? --bender235 (talk) 00:19, 14 September 2016 (UTC)

Great Moments in Relativistic Physics

The Adventures of Buckaroo Banzai Across the 8th Dimension is a vastly underappreciated bit of cinema. It was released in 1984, which is about the time physics started getting really interesting.... Best regards, loupgarous (talk) 18:43, 16 September 2016 (UTC)

Yes, I have it on DVD, and have been using an image of John Whorfin as one of my LiveJournal user avatars since early 2006. Is this apropos of anything in particular? —David Eppstein (talk) 20:23, 16 September 2016 (UTC)

Not really in WP, apart from occasional bubbles of ferment over relativity, whether Einstein fudged the relativistic correction to the orbit of Mercury (versus Newtonian orbital mechanics), things like that. loupgarous (talk) 20:34, 16 September 2016 (UTC)

Honestly I don't know which is worse...

• The idea that Trump's people actually meant to inject the 88 symbolism, or
• The idea that Trump and his people are all so stupid and ignorant that they didn't realize they were doing it by accident. See, of course, User:EEng#Museum_of_Separated_At_Birth,_Pt._2_a.k.a._Life_Imitates_Art.

EEng 18:38, 17 September 2016 (UTC)

Trump's new people are at the heart of the alt-right. There's no way they didn't know. —David Eppstein (talk) 18:43, 17 September 2016 (UTC)

Good point. How about the carpet comment? In my fantasy there's a mole on Trump's staff who suggests ways like that for him to embarrass himself. EEng 18:48, 17 September 2016 (UTC)

Not sure, that one could just be stupidity (aka Trump's razor). —David Eppstein (talk) 18:54, 17 September 2016 (UTC)

• To add to your joy, you'll be happy to know that one of our favorite crazies is active at Paraconsistent_logic. EEng 07:58, 18 September 2016 (UTC)

New developments

Hello,

there are new developments in the section #Graphs_in_topology_and_lemma_separation, but due to the template nature of that section you may have not been notified of these changes. See there also for instruction how best to reply (in order to be informed about future changes in this discussion, you could put the respective page on your watchlist). --Mathmensch (talk) 20:49, 20 September 2016 (UTC)

Extended confirmed protection

Hello, David Eppstein. This message is intended to notify administrators of important changes to the protection policy.

Extended confirmed protection (also known as "30/500 protection") is a new level of page protection that only allows edits from accounts at least 30 days old and with 500 edits. The automatically assigned "extended confirmed" user right was created for this purpose. The protection level was created following this community discussion with the primary intention of enforcing various arbitration remedies that prohibited editors under the "30 days/500 edits" threshold to edit certain topic areas.

In July and August 2016, a request for comment established consensus for community use of the new protection level. Administrators are authorized to apply extended confirmed protection to combat any form of disruption (e.g. vandalism, sock puppetry, edit warring, etc.) on any topic, subject to the following conditions:

• Extended confirmed protection may only be used in cases where semi-protection has proven ineffective. It should not be used as a first resort.
• A bot will post a notification at Wikipedia:Administrators' noticeboard of each use. MusikBot currently does this by updating a report, which is transcluded onto the noticeboard.

Please review the protection policy carefully before using this new level of protection on pages. Thank you.
This message was sent to the administrators' mass message list. To opt-out of future messages, please remove yourself from the list. 17:49, 23 September 2016 (UTC)

Hi

Could you please take a look at the articles about Rock-Olga and Helene Ripa. Any help with improvements etc are welcomed. Regards,--BabbaQ (talk) 21:48, 25 September 2016 (UTC)

golden mean

Hi, You have Undid revision 741944293 by Adam majewski because " " no connection to text of article)" . It is an example of relation between golden ratio and dynamics. You can read about piramids in article. Why do you mean that dynamics is not connected ? Regards. --Adam majewski (talk) 19:03, 30 September 2016 (UTC)

(1) You put that image in the section about the golden ratio conjugate. Nothing in your image seems to be about the relation between the golden ratio and its conjugate. (2) Your image is of a Julia set. The article does not mention Julia sets. (3) Julia sets are a far more WP:TECHNICAL concept than the content of the article at that point. (4) Further, there is no evidence that the choice of the golden ratio as the defining constant for a Julia set has any special significance in dynamics — how does the dynamics described by this Julia set differ from that of any other nearby number? —David Eppstein (talk) 21:40, 30 September 2016 (UTC)