User talk:Lambiam/Archive 18

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The Holy Grail of MHP just got better edit

Here is a short and elementary and complete solution of the MHP, which actually covers the biased host situation just as well as the usual symmetric case. There is no computation of a conditional probability. All we have to do is to consider two kinds of players: a player who in some situations would stay, and a player who in all situations would switch. We show that both kinds of players are going to end up with a goat with probability at least 1/3. In other words, it's not possible to do better than to get the car with probabillity 2/3. But always switching does give you the car with probability 2/3. Hence always switching achieves the best that you can possibly do.

Suppose all doors are equally likely to hide the car, and you choose Door 1.

If you are planning to stick to Door 1 if offered the choice to switch to Door 2, you'll not get the car if it is behind Door 2. In that case Monty would certainly open Door 3, you'll have the choice between Doors 1 and 2, and you'll keep to Door 1. Chance 1 in 3.

Similarly if you are planning to stick to Door 1 if offered the choice to switch to Door 3, you'll not get the car if it is behind Door 3. Probability 1/3.

If on the other hand you are planning to switch anyway, you'll not get the car if it is behind Door 1. Chance 1 in 3.

Altogether this covers every possible way of playing, and however Monty chooses his door: there's always a chance of at least 1/3 that you'll end up with a goat. This means that there is no way you can do better than getting the car with chance 2/3.

We know that "always switching" guarantees you *exactly* a chance of 2/3 of getting the car. I've just shown you that there is no way this can be improved.

Side remark 1: For those who are interested in conditional probabilities, the previous remarks prove that the conditional probabilities of the location of the car (given you chose door x and the host opened door y) will always be in support of switching. Otherwise, we could improve on the 2/3 overall succcess-chance of always switching, by not switching in a situation indicated by the conditional probability of winning by switching being less than 1/2.
Side remark 2: For those who are worried that I did not talk about randomized strategies (e.g. you toss an unbiased coin to decide whether to switch or stay, when you chose Door 1 and the host opened Door 3) it suffices to remark that you could as well have tossed your coin in advance of the host opening a door. Thus this is the same as choosing a deterministic strategy in advance, by randomization. Since any deterministic strategy gives you a goat with probability at least 1/3, the same is true when you choose one such strategy at random.

Of course 20 text-books in elementary probability theory do MHP in a different way, while the previous analysis is only implicit in recent arXiv.org papers (preprints) of A.V. Gnedin. However as a service to wikipedia editors Richard D. Gill (mathematician) will place this analysis on his university home page so there is at least one reliable source for it. Richard Gill (talk) 13:10, 1 July 2011 (UTC)Reply

Lewontin's fallacy AFD edit

Hi. I have a question regarding your AFD comment. I was wondering if you could provide some clarification. Thanks. Guettarda (talk) 18:28, 13 July 2011 (UTC)Reply

Japanese dialect/s edit

I was just wondering why you moved Japanese dialects? Considering that there is more than one, is not the pluralized form more accurate? Also why was there no discussion before the move? Colincbn (talk) 01:16, 14 July 2011 (UTC)Reply

Orphaned non-free image File:HP7part1+2poster.jpg edit

 

Thanks for uploading File:HP7part1+2poster.jpg. The image description page currently specifies that the image is non-free and may only be used on Wikipedia under a claim of fair use. However, the image is currently not used in any articles on Wikipedia. If the image was previously in an article, please go to the article and see why it was removed. You may add it back if you think that that will be useful. However, please note that images for which a replacement could be created are not acceptable for use on Wikipedia (see our policy for non-free media).

Note that any non-free images not used in any articles will be deleted after seven days, as described in the criteria for speedy deletion. Thank you. Sfan00 IMG (talk) 10:57, 18 July 2011 (UTC)Reply

Article's whose AFD you commented in back at AFD a month later edit

Since you commented in the AFD for this article last month, I thought you might want to know its back at AFD again this month. [1] Dream Focus 03:20, 22 July 2011 (UTC) \Reply

Wilma Pang edit

Please have a look at it as someone seems to be trying to delete it again. — Preceding unsigned comment added by 184.164.148.90 (talk) 22:38, 23 July 2011 (UTC)Reply

Lewontin's Argument edit

Fllowing the recen [2] our participation in the dicussion about the title and scope of the article will be apreciated.·ʍaunus·snunɐw· 01:07, 30 July 2011 (UTC)Reply

Harshad number edit

For this edit, I count MHN-10 not MHN-12. Using the same method shown at Harshad number#Multiple Harshad numbers:

  1. 100800000000/9=11200000000
  2. 11200000000/4=2800000000
  3. 2800000000/10=280000000
  4. 280000000/10=28000000
  5. 28000000/10=2800000
  6. 2800000/10=280000
  7. 280000/10=28000
  8. 28000/10=2800
  9. 2800/10=280
  10. 280/10=28

and stops, because 28/10 is not an integer. In general, 1008·10n is MHN-(n+2) not MHN-(n+4). Am I missing something? Art LaPella (talk) 18:41, 2 August 2011 (UTC)Reply

Technology Report edit

Hey Lambiam. Thanks for your copyedits - I'm terrible at writing quickly but without error. What did you think about the article as a whole? I've just got to add bugs, BRFAs, and expand the links in the In brief section. Is it readable? Understandable? Interesting? I shan't be offended :) Regards, - Jarry1250 [Weasel? Discuss.] 20:34, 14 August 2011 (UTC)Reply

AFD redirect edit

Hi, with regard to the OUTeverywhere AFD, there have been two prior AFDs (as per the article talk page and my note in the current AFD). There may be some confusion as one of the past AFDs was for Wikipedia:Articles for deletion/Out (website) which is actually the same article. Cheers (talk) 21:03, 16 August 2011 (UTC)Reply

The Last Hurrah edit

Hi there! You removed my line in the summary of the article "The Last Hurrah", because you didn't understand what "no longer in publication" meant. No store sells the book new anymore, not even the publisher. You can only buy it used. That's what I mean by "no longer in publication". Soren121 (talk) 21:52, 17 August 2011 (UTC)Reply

A discussion... edit

...which may interest you: [3] Beyond My Ken (talk) 21:13, 31 August 2011 (UTC)Reply

Christogram edit

It may sound theoretically nice to change lunate sigma from being Latin "C" to the correct Unicode character, but if few people's browsers actually display the technically-correct Unicode character, then I'm not sure that the article was actually improved... AnonMoos (talk) 16:43, 13 September 2011 (UTC)Reply

A barnstar for you! edit

  The Teamwork Barnstar
For dealing with the User:Marshallsumter issues. Cerejota If you reply, please place a {{talkback}} in my talk page if I do not reply soon. 04:43, 15 September 2011 (UTC)Reply

Abdi İpekçi Street ->Avenue edit

Hı! We cannot translate "cadde" in general as "avenue". Avenue means a broad street, especially one bordered by trees.[4] Abdi İpekçi Caddesi is a narrow oneway street. İstiklal Caddesi may be named avenue, because it opens to a big place and it is not narrow. It is wise to revert your move. Cheers. CeeGee (talk) 10:03, 20 September 2011 (UTC)Reply

While streets called "avenue" are usually broad streets, especially in the U.S., not all streets called "avenue" are necessarily broad. Originally just meaning "access road", one of its meanings is "thoroughfare", which corresponds to how cadde is used in Turkey. Istanbul was not designed for car traffic, and unfortunately some major thoroughfares are now uncomfortable narrow, but, narrow and one-way as it is, Abdi İpekçi Caddesi is a thoroughfare. In any case, I think it is better to translate cadde uniformly for a variety of reasons, including the existence of streets whose names are differentiated by sokak versus cadde (e.g., Abdi İpekçi Sokak as a side street of Bağdat Caddesi in Fenerbahçe, and another one in İçerenköy). I also notice that Şişli Belediyesi uses "Abdi Ipekci Avenue" in English texts,[5] as does Hürriyet Daily News.[6]  --Lambiam 10:35, 20 September 2011 (UTC)Reply

Thanks for your detailed explanations. Unfortunately, translations made by officials in our country are not always correct, sometimes also silly. Cheers. CeeGee (talk) 11:53, 20 September 2011 (UTC)Reply