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riddles >> general problem-solving / chatting / whatever >> Guardian Article
(Message started by: THUDandBLUNDER on Sep 6th, 2004, 8:49pm)

Title: Guardian Article
Post by THUDandBLUNDER on Sep 6th, 2004, 8:49pm
But for the nonsensical first paragraph, an informative article (http://www.guardian.co.uk/life/science/story/0,12996,1298812,00.html).


Title: Re: Guardian Article
Post by TenaliRaman on Sep 6th, 2004, 10:53pm
Nice Article T&B.  :)
Related Read :
Riemann and Louis De Branges (http://www.math.purdue.edu/ftp_pub/branges/apology.pdf)

Title: Re: Guardian Article
Post by THUDandBLUNDER on Sep 7th, 2004, 3:04am
I don't think I am setup to access FTP files.

Is Purdue apologising for de Branges' recent claim to have proved RH?


Title: Re: Guardian Article
Post by BNC on Sep 7th, 2004, 7:59am
T&B,

You can get it here (http://www.yousendit.com/d.aspx?id=EE7C9ECEF1523133B8A548CB47395F66)

Title: Re: Guardian Article
Post by THUDandBLUNDER on Sep 9th, 2004, 12:20am

on 09/07/04 at 07:59:44, BNC wrote:
T&B,

You can get it here (http://www.yousendit.com/d.aspx?id=EE7C9ECEF1523133B8A548CB47395F66)

Thanks, BNC. In fact, I already had it on my HD.


Title: Re: Guardian Article
Post by Barukh on Sep 9th, 2004, 1:23am
This thread follows another one (http://www.ocf.berkeley.edu/~wwu/cgi-bin/yabb/YaBB.cgi?board=riddles_general;action=display;num=1086805467) on the site. As I understood, not much has changed from then…

An interesting point is referring to Poincare conjecture. This Russian Perelman seems to be a character opposite to de Branges; the latter is certainly claiming to have found the proof, he does want a reward, and he certainly wants to talk to the media.  ;D

Title: Re: Guardian Article
Post by THUDandBLUNDER on Dec 8th, 2006, 6:08am
http://technology.guardian.co.uk/news/story/0,,1967226,00.html

Title: Re: Guardian Article
Post by Icarus on Dec 8th, 2006, 3:29pm
Is there supposed to be an article with that link? All I get are the buttons and banners.

Title: Re: Guardian Article
Post by THUDandBLUNDER on Dec 8th, 2006, 5:08pm

on 12/08/06 at 15:29:05, Icarus wrote:
Is there supposed to be an article with that link? All I get are the buttons and banners.

Seems that one can't link to it directly.
Need first to go to http://technology.guardian.co.uk/
and it is at present the first article, entitled 'Cybercriminals sign student 'sleepers'.

Title: Re: Guardian Article
Post by towr on Dec 9th, 2006, 5:38am

on 12/08/06 at 17:08:23, THUDandBLUNDER wrote:
Seems that one can't link to it directly.
Copying/pasting the link works.
If you already clicked, copy/paste and put a ? behind it. (Or clear the cache, whichever is easiest)

Title: Re: Guardian Article
Post by ThudanBlunder on Jun 15th, 2008, 6:02am
http://education.guardian.co.uk/higher/news/story/0,,2284904,00.html

Title: Re: Guardian Article
Post by towr on Jun 15th, 2008, 7:05am

on 06/15/08 at 06:02:06, ThudanBlunder wrote:
http://education.guardian.co.uk/higher/news/story/0,,2284904,00.html
That seems to be a response to
http://education.guardian.co.uk/higher/news/story/0,,2284409,00.html
Which seems to be a response to something else again..


heh

Quote:
As far as "financiers, consultants, marketers, publicists and lawyers" are concerned, I would put them with the hairdressers and phone hygienists on Douglas Adams' doomed spaceliner.
Andy Smith

Title: Re: Guardian Article
Post by ThudanBlunder on Jun 15th, 2008, 8:43am

on 06/15/08 at 07:05:38, towr wrote:
That seems to be a response to
http://education.guardian.co.uk/higher/news/story/0,,2284409,00.html
Which seems to be a response to something else again..

This (http://www.guardian.co.uk/commentisfree/2008/jun/06/maths.alevels)

Title: Re: Guardian Article
Post by ThudanBlunder on Jul 26th, 2009, 12:46am
http://www.guardian.co.uk/science/blog/2009/jul/24/bacteria-computer

Title: Re: Guardian Article
Post by ThudanBlunder on Aug 23rd, 2010, 6:03am
http://www.guardian.co.uk/media/2010/aug/22/worlds-hardest-sudoku

Title: Re: Guardian Article
Post by towr on Aug 23rd, 2010, 6:11am

on 08/23/10 at 06:03:33, ThudanBlunder wrote:
http://www.guardian.co.uk/media/2010/aug/22/worlds-hardest-sudoku
If it can't be solved by logic alone it's not  a very good sudoku.
Do you have a link for where they posted the sudoku itself? Never mind I just have to click the partial image..

[e] http://www.sudokusolver.co.uk/ cannot solve it by (its) logic alone, but with a bit of guessing it finds a solution easily enough. [/e]

Title: Re: Guardian Article
Post by ThudanBlunder on Aug 23rd, 2010, 7:15am

on 08/23/10 at 06:11:39, towr wrote:
If it can't be solved by logic alone it's not  a very good sudoku.

I thought all sudokus involved some luck and guesswork, which is one reason why I never try them.  
Same goes for Minesweeper and FreeCell, although there is a variant of the former that requires skill alone.
And there is an example of the latter (#11982) that is impervious to luck or skill!


Title: Re: Guardian Article
Post by towr on Aug 23rd, 2010, 7:39am

on 08/23/10 at 07:15:37, ThudanBlunder wrote:
I thought all sudokus involved some luck and guesswork, which is one reason why I never try them.  
No, all the ones I have had experience with could be solved using (usually simple) logical rules. I usually even do it without keeping a record of which digits are still allowed in a cell (the simple way to solve one is just to start with 1-9 in each cell, and then eliminate numbers. If a number exist in only one cell in a row, column or block, then you know that cell must contain that number and can eliminate it from the other sets in the same block, row and columns).
If guessing is needed, then it's simply a bad sudoku, in my opinion.

[edit]If you add two starting values in this puzzle, B6=4, I9=4, then you can solve it by logic alone (and so can http://www.sudokusolver.co.uk/ which can give you a trace of the process, and even step by step explanation)[/edit]

Title: Re: Guardian Article
Post by SMQ on Aug 23rd, 2010, 7:49am

on 08/23/10 at 07:15:37, ThudanBlunder wrote:
I thought all sudokus involved some luck and guesswork, which is one reason why I never try them.  
Same goes for Minesweeper and FreeCell, although there is a variant of the former that requires skill alone.

There are two schools of thought there.  Certainly a lot of progress can be made by straightforward deductions of the form "this cell can only be an X" and "the only place in this row/column/square for an X is this cell", and keeping careful track of the possibilities for each cell is a prerequisite for successful solving.  But for all but the easiest sudoku, those two direct deductive rules won't be sufficient, and here's where the debate comes in.

One group, the "purists", of which it sounds like towr is a member, focus on developing ever-more-complex deductive rules involving multiple related cells.  (See, for example, here (http://www.angusj.com/sudoku/hints.php).)  If none of the logical rules they're aware of is applicable and they are unable to make further progress without trial-and-error, then declare the puzzle "broken" and a waste of time. ;D

The other group, the "casual solvers", only try to remember and apply the most-often-needed deductive rules, and see no dishonor in applying trial-and-error when they reach their deductive limit.  So long as the puzzle has a unique solution the casual solvers find it acceptable, even if they gain no particular insight or skill beyond accurate bookkeeping. ;D

For myself, I don't think it's as cut-an-dry as either group would like to believe.  The more complicated a deductive rule is--the more it relies on interactions and contradictions among 4, 5 or more cells--the more it sounds like trial-and-error without writing down the intermediate results. ;)

--SMQ

Title: Re: Guardian Article
Post by towr on Aug 23rd, 2010, 7:58am

Quote:
One group, the "purists", of which it sounds like towr is a member, focus on developing ever-more-complex deductive rules involving multiple related cells.
Well, then I am clearly not a member of the "purists".
Besides, if you allow ever-more-complex rules, then trial and error must be valid. Because quite logically, it's just an application "if A[i][j]=X isn't part of the solution, then for some Y != X, A[i][j]=Y is part of the solution". It's a very simple rule, but also a very complex one to apply, because it can go wrong very deep down the line.

Title: Re: Guardian Article
Post by ThudanBlunder on Aug 23rd, 2010, 10:21am
Interestingly, the software required only 15 guesses to solve the Guardian puzzle, compared with 19 guesses for the most difficult (http://www.sudokusolver.co.uk/sudokuStats.html) one in its database.

But different guesswork/algorithms may produce somewhat different numbers.

Title: Re: Guardian Article
Post by JiNbOtAk on Aug 24th, 2010, 7:22am

on 08/23/10 at 07:49:57, SMQ wrote:
 The more complicated a deductive rule is--the more it relies on interactions and contradictions among 4, 5 or more cells--the more it sounds like trial-and-error without writing down the intermediate results. ;)


I used to believe that the purist's approach is the best, though I have to admit I usually resort to the casual method more often than not. However, in hindsight, after witnessing a friend who is considered a master sudoku solver (among us anyway), I tend to agree with SMQ. When it gets to eliminating this and that which involves more than 5 cells, what the heck, might as well start guessing. Unless, of course, you're equipped with a partitioned brain thats capable of multitasking several possibilities simultaneously.

Title: Re: Guardian Article
Post by towr on Aug 24th, 2010, 7:33am
Well, my position is that as soon as you need to start guessing, you may as well just let a computer do it. Saves a lot of paper, too.

Title: Re: Guardian Article
Post by ThudnBlunder on May 25th, 2011, 3:38pm
http://www.guardian.co.uk/world/2011/may/25/china-prisoners-internet-gaming-scam

Title: Re: Guardian Article
Post by ThudnBlunder on Sep 26th, 2011, 11:38pm
http://www.guardian.co.uk/science/mathematics

Title: Re: Guardian Article
Post by ThudnBlunder on Nov 20th, 2011, 1:32pm
http://www.guardian.co.uk/technology/2011/nov/20/voice-recognition-apple-siri

Title: Re: Guardian Article
Post by vjlenin on Aug 19th, 2012, 1:51am
Siri is one of the most advanced of voice recognition software today. I love it in fact. Check out the comparison of Siri to other voice command systems like Tellme and Google voice.



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