Talk:Four color theorem/GA1

GA Review
The edit link for this section can be used to add comments to the review.''

Reviewer: Pyrotec (talk) 11:38, 7 October 2009 (UTC)


 * Starting review. Pyrotec (talk) 11:38, 7 October 2009 (UTC)


 * It's not clear to me whether this is a "drive by" nomination, as the nominator does not appear to have contributed to the article. Anyway, I'm going to review this against WP:WIAGA. Pyrotec (talk) 15:14, 9 October 2009 (UTC)

Initial comments

 * This article is possibly reasonably close to GA-status so I'm not going to quick fail it; but I suspect that this article is likely to need some work doing during an "On Hold" period in order to comply with WP:WIAGA.
 * The article is reasonably well-referenced in several sections, but not all sections have references and not all paragraphs have references. The article uses Harvard references rather than footnote style references, but that is permitted. I only comment since I don't often see it in WP:GANs; but more referencing is likely to be needed.
 * In particular, I don't think that this article is necessarily written to make life particularly easy for the non-specialist reader. Technical terms and wikilinks sometimes appear to be used as barriers to keep out "outsiders" rather than to inform the non-specialist. I will come back to this later on.
 * Please assume good faith. It is entirely likely that some of the editors of this article thought, incorrectly, that a wikilink would suffice to explain a technical term rather than redundantly providing an inline gloss, but I'm sure it was not their intention to prevent understanding. —David Eppstein (talk) 19:45, 11 October 2009 (UTC)
 * Well I'll pull out of this review if that is what you are asking for. Pyrotec (talk) 19:52, 11 October 2009 (UTC)
 * Of course not. All I'm asking is that you be a little more careful about avoiding ad hominem wording in your otherwise very useful critique. —David Eppstein (talk) 20:10, 11 October 2009 (UTC)

I will now consider the article in more depth, section by section, but leaving the WP:Lead until last.

Pyrotec (talk) 19:49, 9 October 2009 (UTC)

At this point I'm only concentrating on "problems", the rest will be picked up in the overall summary.


 * Precise formulation of the theorem -
 * (Thomas 1998; Wilson 2002) are, respectively, a 12-page report and a book. The relevant page or page numbers should be cited.
 * I would suggest that the two diagrams need an improved (simple) explantion). The four colours appear to be mapped onto a pyramid with the edges representing the boundaries between the regions and the regions represented by the vertics: we suggests going from a one-dimensional structure into a three-dimensional structure. There is no explantion of whether the vertices are intended to be located at the centroid of each region: in the red region this could be inferred, in the other regions this point is uncertain.
 * The three dimensional appearance is illusory, and the locations of the vertices within the regions are unimportant; all that matters is the abstract pattern of incidences between vertices and edges. I've reworded the final paragraph of this section in an attempt to make this more clear. —David Eppstein (talk) 19:40, 11 October 2009 (UTC)
 * Thanks, it is much improved. ✅ Pyrotec (talk) 19:44, 11 October 2009 (UTC)


 * History -
 * Early proof attempts -
 * (Wilson 2002) is a book. The relevant page or page numbers should be cited.
 * (Thomas 1998) is a 12-page report. The relevant page or page numbers should be cited. ✅ Pyrotec (talk) 19:38, 15 October 2009 (UTC)
 * There is no reference for the Five color theorem.
 * There are no references for Danilo Blanuša finding an original snark and the Hadwiger conjecture.


 * Proof by computer -
 * Many of the cited references are books and appart from two exceptions no page numbers are given.


 * Simplification and verification -
 * Many of the cited references are books. The relevant page or page numbers should be cited.


 * Summary of proof ideas -
 * This section is based on (Appel & Haken 1989, the relevant page numbers should be cited.


 * False disproofs -
 * The first paragraph cits (Wilson 2002), which is a book, the relevant page or page numbers should be cited.
 * The final sentence is a statement that needs a citation; the other sentences appear to be explanations.


 * Generalizations -
 * Much of this is adequately cited using (Weisstein), however:
 * The final paragraph cits (Wilson 2002), which is a book, the relevant page or page numbers should be cited.

....to be continued. Pyrotec (talk) 11:59, 11 October 2009 (UTC)
 * WP:Lead -
 * The WP:Lead appears to be compliant. Pyrotec (talk) 19:45, 15 October 2009 (UTC)


 * Some references like (Cayley 1879) do not give page numbers, Please provide them.-- Redtigerxyz Talk 12:47, 13 October 2009 (UTC)

Overall summary
GA review – see WP:WIAGA for criteria


 * 1) Is it reasonably well written?
 * A. Prose quality:
 * B. MoS compliance:
 * 1) Is it factually accurate and verifiable?
 * A. References to sources:
 * B. Citation of reliable sources where necessary:
 * C. No original research:
 * 1) Is it broad in its coverage?
 * A. Major aspects:
 * B. Focused:
 * 1) Is it neutral?
 * Fair representation without bias:
 * 1) Is it stable?
 * No edit wars, etc:
 * 1) Does it contain images to illustrate the topic?
 * A. Images are copyright tagged, and non-free images have fair use rationales:
 * B. Images are provided where possible and appropriate, with suitable captions:
 * 1) Overall:
 * Pass or Fail:
 * 1) Is it stable?
 * No edit wars, etc:
 * 1) Does it contain images to illustrate the topic?
 * A. Images are copyright tagged, and non-free images have fair use rationales:
 * B. Images are provided where possible and appropriate, with suitable captions:
 * 1) Overall:
 * Pass or Fail:
 * B. Images are provided where possible and appropriate, with suitable captions:
 * 1) Overall:
 * Pass or Fail:
 * Pass or Fail:

I would hope that someone will undertake the necessary changes and resubmit this article to WP:GAN in due course. It needs, in my oppinion, only page numbers for book citations to make GA. Pyrotec (talk) 20:47, 29 October 2009 (UTC)