Misplaced Pages

Revision as of 20:56, 8 October 2011

This is the talk page for discussing WikiProject Statistics and anything related to its purposes and tasks.

Put new text under old text. Click here to start a new topic. New to Misplaced Pages? Welcome! Learn to edit; get help. Assume good faith Be polite and avoid personal attacks Be welcoming to newcomers Seek dispute resolution if needed Shortcuts WT:WPSTAT WT:WPSTATS

Archives: 1, 2, 3, 4, 5, 6, 7Auto-archiving period: 3 months

	This project page does not require a rating on Misplaced Pages's content assessment scale. It is of interest to the following WikiProjects:
Statistics This page is within the scope of WikiProject Statistics, a collaborative effort to improve the coverage of statistics on Misplaced Pages. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.StatisticsWikipedia:WikiProject StatisticsTemplate:WikiProject StatisticsStatistics

Archives

Archive 1: March 2008 – August 2008 Archive 2: August 2008 – July 2009 Archive 3: July 2009 – May 2010 Archive 4: May 2010 –

This page has archives. Sections older than 90 days may be automatically archived by Lowercase sigmabot III when more than 3 sections are present.

Overall and general population

I noted in the example on the 1age standardisation' entry that the heart disease rates amongst indigenous Australians ae compared to the general population and to the overall population. Are the general population and the overall population the same?

This article seems confusingly written. How can patients who have not completed the design be included in the assessment of efficacy? How can patient dropout break the initial randomization? These are concepts that sound like nonsense unless further explained. Certainly, dropout may be greater in the treatment group due to more severe side effects, but the dropout rate should be the same in the control group, and in any case it is not clear that the side effects should be correlated with the treatment effect. Including untreated patients in the assessment of treatment efficacy is certain to bias against the efficacy measure, so this is an overreaction strategy that seems entirely unnecessary in a proper experimental design with a placebo control group. ----

Should the curve and surface fitting web site zunzun.com be discussed anywhere in Misplaced Pages?

Should the curve and surface fitting web site zunzun.com be discussed anywhere in Misplaced Pages? It seems relevant to some of the statistics topics.

Links to zunzun.com are banned from Misplaced Pages. Such discussions are useless no matter how relevant.

Category rename

There is a discussion of renaming category Category:Experimental design to Category:Design of experiments: see and contribute in this discussion.

Two envelopes problem, two children problem

Having fought for two years on the Monty Hall problem, almost getting banned from wikipedia for OR and COI, I am looking for a new brawl, and am getting stuck into the two envelopes problem. Have been accused of gross arrogance and incivility within one day (practice makes perfect! I didn't want to waste time with ritual dances but went straight to the nitty gritty). There is a big problem with that page, that a lot of people have been writing up their own common sense solutions (both sensical and nonsensical) but almost no one actually reads the sources. I just wrote up two mainsteam solutions to two main variants of the two envelopes problem, both "out of my head", ie without reliable sources. (Very evil of course, very un-wikipedian). After all, I have been talking about these problems with professional friends for close on fourty years now, and setting them as exam questions, talking about them with students, without ever actually carefully reading published literature on the problems.

It's un-wikipedian only if some content is disputed or you aspire to class B (or C, may vary across wikipedia), or both. I believe you have both. ...

Maybe some of you folk here can get access to some of those papers in journals where you have to pay a big tax to the publishing company before you can actually read the pdf. That would be useful.

Looks like the two children problem is equally much a mess.

Of course I could be completely wrong that what I think are the solutions to the two main variants of the two envelopes problems are indeed the solutions, or for that matter, are correct at all... Richard Gill (talk) 08:12, 3 May 2011 (UTC)

The latest contributions to the Talk page for two envelopes problem are mostly by me. And two of the sections on the page itself were hurriedly and entirely written purely as uncited "own research" by me. , .

Well: I think I report the accepted wisdom / folklore in my community. What does the community think? Does the community know good references? Richard Gill (talk) 14:50, 3 May 2011 (UTC)

-The facts are telling: there is so much "accepted wisdom / folklore" and reference to reliable sources is challenging or impossible (and not primarily because some journal content is tax-sheltered, so to speak). Previously I have noted WP troubles handling pedagogy and illustration. Others have said the same regarding exposition (partly in and about Monty Hall arbitration). It is inevitable that distinction between original research and original pedagogy, original illustration, or original exposition is contentious. Yet we may all agree that Misplaced Pages should include entries such as "Monty Hall problem" rather than "'The Monty Hall Problem' in print".

-It's possible that the way is clear to writing "Bertrand's paradox" or "Newcomb's paradox" well and without much dispute. If so, I guess it's because there is a locus classicus in the writings of J.Bertrand or S.Newcomb, not only penned but also discussed in print before any WP editor was born.

-Consider the long "See also" sections of some articles on puzzles (problems, paradoxes, etc). No doubt this cornucopia has been generated partly by some teachers and columnists tweaking the corpus. Some have presented wholly new scenarios, with or without coining new titles, while others have presented their own revised versions for their own purposes yet under the old names. Now after a few generations of mass higher education, we have many editors who cut their own eye teeth on one puzzle or another. Indeed, we may have thousands who cut their eye teeth as economics, probability, statistics, logic, or philosophy students, along with hundreds for whom it was their eye teeth as teaching assistants or faculty members.

-I think we may agree that it can be good pedagogy to adapt one of these puzzles to a local purpose --specific to the study session, the course of lectures, or the article for in a teaching journal (if not for wikipedia beyond Start class). Except in the teaching journal it may be good practice to do so either with or without changing the scenario (goats for asses; envelopes for wallets) and with various attitudes toward previous authors (credit Bertrand by calling the puzzle Bertrand's, nod to the revisions by not naming him).

-Collectively we have learned to think in terms of different versions of these different puzzles and their solutions. For some of us and some of the puzzles, that happened before anyone wrote any version into the literature.

-Today I don't have any optimistic or encouraging suggestion. Evidently I have some ideas for an Essay but I admit that I don't yet see it taking any particular shape. I'm not optimistic about that either.--P64 (talk) 17:57, 3 May 2011 (UTC)

Food for thought. No easy solution. Indeed worth an Essay! Richard Gill (talk) 06:52, 4 May 2011 (UTC)

I have collected my thinkings on the two envelopes problem on my Talk page at . This must all be known. References??? Richard Gill (talk) 14:53, 8 May 2011 (UTC)

I've written a new essay on Two Envelopes Problem on my talk page: . It's called TEP, Anna Karenina and the Aliens movie franchise. Richard Gill (talk) 16:42, 20 July 2011 (UTC)

Notation

Several other contributors have mentioned the inconsistency of notation for transposes. Sometimes we have ', sometimes $^T$. At one point (affine transformations) we have a 'dot product' for the same thing. Could we please have consistency? I personally like $^{\rm T}}$, followed by $^T$. Econometricians like ' as T tends for them to indicate time. — Preceding unsigned comment added by 85.221.177.233 (talk) 09:50, 13 July 2011 (UTC)

It's a fact of life that different *sources* use different notation. Sooner or later the reader is going to be confronted with this. Now if there is a small group of wikipedia articles on closely related topics that refer to one another a great deal, and which rely on much the same collection of sources, then uniformity of notation within this group would be sensible and an individual editor can seek consensus among the editors of those articles for a preferred notation. But in general I doubt we would ever agree on a preferred notation nor be able to enforce it; and anyway there will be readers coming to statistics articles from physics or from pure mathematics or whereever, who will have to be told specifically "where ... denotes transpose". Richard Gill (talk) 16:54, 20 July 2011 (UTC)

I am a big fan of notational consistency and I would like to see it across large rather than small groups of related articles and across wide rather than narrow reference. For example, all of the articles on named probability distributions might use plain, bold, and italic fonts consistently; lower and uppercase letters; Roman and Greek alphabets; a or k as an integer parameter, or not. For example of wide reference, articles that use particular Poisson distribution(s) should (try to) use the same notation as does Poisson distribution—same use of 'k' and lambda, for instance. The only question should be how hard to 'try'. --P64 (talk) 22:58, 20 July 2011 (UTC)

May be, but a major question arises in respect to sources ... and after all a major tenet of Misplaced Pages is provision of adequate reference to sources ... it may be best in some cases to match notation to a specific sources reference, so that things can be easily checked. Of course this is only really relevent where there are several parameters where things like m, n, M ,N are switched round in external sources. And, as for example WP:REFB#Good references suggests that it it not good to use other Misplaced Pages articles as sources, it may in some cases be best to restate things like the pmf of the Poisson distribution (in a local notation if necessary) rather than relying entirely on cross-refs to other articles. Melcombe (talk) 08:50, 21 July 2011 (UTC)

I certainly do support notational consistency when there are a lot of articles referring to one another a great deal. People who feel this is important should try on a few important cases while the lazy or indifferent watch to see how it is received by other editors. Richard Gill (talk) 12:48, 16 August 2011 (UTC)

Deletion proposal - Sampling variogram

The AfD proposal for Sampling variogram has been relisted ... please contibute at Misplaced Pages:Articles for deletion/Sampling variogram . Melcombe (talk) 09:17, 15 July 2011 (UTC)

"Tail" is nowhere defined

The term "tail" is used in many places in the project where distributions are discussed. For those of us with experience with distributions, the term is an everyday term like "lunch", but for many it is not well understood. I'm not sure where would be the best place to introduce the term and welcome suggestions. Could it merit its own article? Jojalozzo 02:56, 25 July 2011 (UTC)

There is the article Heavy-tailed distribution which might give some ideas. Dmcq (talk) 08:20, 25 July 2011 (UTC)

Thinking about it there is room I think for a special article. The standard deviation article seems to assume just the normal distribution and I think something should be done about its table showing things like probability of greater than 5 standard deviations. Dmcq (talk) 08:25, 25 July 2011 (UTC)

Renaming discussion regarding article Copula (statistics)

The proposed renaming being discussed at Talk:Copula (statistics)#Requested move may be of interest to members of this WikiProject. Favonian (talk) 08:21, 2 August 2011 (UTC)

Merge help requested

I was going to ask for comment from statistics folks about whether to merge Heavy-tailed distribution with Fat-tailed distribution at Talk:Heavy-tailed distribution so I could merge if you thought it was a good idea. Then it occurred to me that I wouldn't be able to do the merge anyway since I don't know statistics very well. So, I'll leave this whole issue to WikiProject Statistics, if I may. Thank you, D O N D E groovily Talk to me 01:41, 6 August 2011 (UTC)

Economic statistics

Please see Talk:Economic statistics for discussion of the future of the Economic statistics article. Melcombe (talk) 08:46, 5 September 2011 (UTC)

The Quartile article needs some help

The second sentence in the lead doesn't make sense. There are also some worrying concerns in the Talk page. -- Dandv 08:56, 8 September 2011 (UTC)

Featured article candidate

The article Shapley–Folkman_lemma is nominated for Featured Article status, and the usual Featured-Article reviewers are not mathematicians. Therefore, your comments would be especially valuable, particularly for deciding whether the article meets the FA criteria. Your criticism/suggestions/bold improvements would all be welcome.

Probabilists are especially needed! :)

1. Please help with the 2-paragraph section on probability_and_measure_theory, which is written in summary style. Is it okay to say that the component measures are defined on the same probability space, or is it better to say that they are defined on the same (finitely) measureable space. (I vote for the latter ....)
2. Probabilists may enjoy the applications to random sets!

The SF lemma was used recently for a statistical article in Econometrica, but it seems to be under-used/ignored in statistics.  Kiefer.Wolfowitz 19:15, 30 September 2011 (UTC)

Thanks for your help, in my hour of need ....  Kiefer.Wolfowitz 19:15, 30 September 2011 (UTC)

UPDATE  Kiefer.Wolfowitz 03:32, 1 October 2011 (UTC)

In advanced measure-theory, the Shapley–Folkman lemma has been used to prove Lyapunov's theorem, which states that the range of a vector measure is convex. Here, the traditional term "range" (alternatively, "image") is the set of values produced by the function. A vector measure is a vector-valued generalization of a measure; for example, if p₁ and p₂ are probability measures defined on the same measurable space, then the product function (p₁, p₂) is a vector measure, where (p₁, p₂) is defined for every event ω by

(p₁, p₂)(ω)=(p₁(ω), p₂(ω)).

1. Tardella (1990, pp. 478–479): Tardella, Fabio (1990). "A new proof of the Lyapunov convexity theorem". SIAM Journal on Control and Optimization. 28 (2): 478–481. doi:10.1137/0328026. MR 1040471. {{cite journal}}: Invalid |ref=harv (help)

Market survey discussion

A group of which am a member need help regarding the reliability of market surveys and hacve posted a request for inpedendent advice at Misplaced Pages:Reliable_sources/Noticeboard#Using_reports_of_market_research_surveys. Since market surveys are a branch of applied statistics, could I request input from members of the statitics group. Martinvl (talk) 07:30, 4 October 2011 (UTC)

Misplaced Pages:Requests_for_comment/Kiefer.Wolfowitz

The community is invited to participate in a request for comment about my editing: WP:Requests_for_comment/Kiefer.Wolfowitz.  Kiefer.Wolfowitz 20:54, 8 October 2011 (UTC)

• Project-Class Statistics pages
• NA-importance Statistics pages
• WikiProject Statistics articles