Talk:Simulated annealing

message: There's a page sitting in Simulated annealing/Temp that hasn't seen any significant activity since it was created in October 2004, and isn't linked to anywhere. Does anyone know what's up with it? Bryan 07:10, 29 May 2005 (UTC)
thread_title: Old temp page still in use?

message: Hello. Wasn't simulated annealing introduced first in the article:
Metropolis,N., A. Rosenbluth, M. Rosenbluth, A. Teller, E. Teller, "Equation of State Calculations by Fast Computing Machines", J. Chem.Phys.,21, 6, 1087-1092, 1953. 
?
:As I understand it, no. The Metropolis algorithm is a way of sampling from a distribution
::P(x) = {1 \over Z} \exp(-\beta E(x)). 
:for some value of inverse temperature \beta and for some energy function E that is a function of a vector x. It was typically used to computed expected values of functions over x. I believe that \beta was held fixed. Kirkpatrick realized (and proved) that if \beta decreased slowly as time approaches infinity, then the expected value of x approaches the global minimum of E. -- hike395 02:01, 4 Jun 2005 (UTC)
thread_title:  Credit for Metropolis et al? 

message: ... using simulated annealing. i have recently suggested that the cooling process could be initiated by slowly raising the minimum amount of reference information for matured articles with software aids like combo-boxes for reference type, etc. on top or instead of the underused comment line. (http://thread.gmane.org/gmane.science.linguistics.wikipedia.misc/25805) that should cool down at least vandals or scatterbrains... ;). ok let's hear more opinions. -- Kku 09:30, 7 December 2005 (UTC)
thread_title:  let's cool down wp a bit 

message: It seems to me that the general description of the algorithm could be simplified greatly if the metallurgy metaphor was dumped for a paragraph.
I'd add something like:
Simulated Annealing is a search process that has a better chance at finding global maxima than simple hill climbing.  This is because at the beginning of a space search it's random steps are very large and become smaller as the search continues until finally the algorithm decides on a local maxima from the best place it has found in the space.
It's a little rough because I'm terrible at describing algorithms, but it frames the concept in terms of another space search technique that the reader would either A) be familiar with or B) probablly able to understand a little bit more easily.
Would a paragraph like this be welcome?
:I would favour such a change. Most people learning about simulated annealing are more likely to have already learned about hillclimbing than to have learned about metallurgical physics, although it's a vivid metaphor. I think it also gets across the point that simulated annealing is a search algorithm, and not some kind of physical simulation. Deco 23:15, 15 May 2006 (UTC)
replies: text: I do not favor such a change. The pedagogy of this article is consistent and very good at worst. since there is nothing factually wrong with this section, I vote that it stays in. 64.134.235.11 (talk) 20:45, 7 November 2012 (UTC)
thread_title:  Metaphor too complicated? 

message: Currently the article says:
The initial temperature must be large enough to make the uphill and downhill transition probabilities about the same. To do that, one must have some estimate of the difference e' − e for a random state and its neighbours.
So far this is the best advice I've found on the subject of choosing an initial temperature, and it still doesn't spell out how exactly I do it - the author seems to know but isn't giving details. I'd like to see some added content at least giving an example of how to choose an effective initial temperature. Deco 23:24, 15 May 2006 (UTC)
replies: text: For what it's worth, I just found out about the paper "Computing the Initial Temperature of Simulated Annealing" which probably answers my question. :-) Maybe a good reference to add? Deco 23:28, 15 May 2006 (UTC)
replies: text: If you add it, I think you should link it as http://dx.doi.org/10.1023/B:COAP.0000044187.23143.bd, which is a more permanent URL. Itub 21:24, 16 May 2006 (UTC)
thread_title:  Initial temperature 

message: This section reads highly unencyclopedic:
:If the modified Simulated Quenching (SQ) works, fine, but it should not be called SA. SA is often used for hard problems where the chances are reduced for being trapped in local minima. SA also is used in problems with complex constraints since the method of rejection is simply applied to keep the sampling within the constrained region(s). In practice, when the need is clear to use a sampling technique, it is best to do at least a few long runs with SA, and then use SQ modifications to speed up calculations as long as the same results are achieved. To apply any generic sampling technique like SA over many classes of nonlinear problems, it should be expected that tuning of some basic search parameters will be required.
First, the first sentence is (oddly worded) POV. Second, the section doesn't explain what SQ is in comparison to SA. Third, the second half reads like a how-to. I don't know SQ so I can't modify this, but maybe someone here can. Thanks! ~ trialsanderrors 18:56, 1 September 2006 (UTC)
thread_title: Quenching

message: How do you tell that "Therefore the goal is to bring the system, from an arbitrary initial state, to a state with the minimum possible energy"?  --Javalenok 22:43, 11 November 2006 (UTC)
thread_title:  Energy conservation :) 

message: The date that Kirkpatrick et al. came up with simulated annealing is wrong.  I don't have the information handy as to when they first published/presented the idea, but I know it was before 1983, because during the summer of 1982 I worked with Scott Kirkpatrick on some applications of simulated annealing to circuit design, and they had already been working with the idea for a little while at that point.  141.149.211.196 20:42, 6 April 2007 (UTC)
replies: text: It may be hard to document the date they "came up" with simulated annealing. What we have is the date of the oft-cited Science paper about it. Maybe just rephrasing the statement so that it reads "first published by Kirkpatrick in 1983..." or something to that effect, rather than saying "invented" (of course, if you know of an earlier publication feel free to add it!). --Itub 07:56, 10 April 2007 (UTC)
thread_title:  Dates need to be corrected 

message: The "In Plain English" section is inadequate for several reasons.
First, it does not try to describe SA; those comments could fit almost any meta-heuristic.   SA is a specific meta-heuristic, that moves from state to state according to a fairly specific method, that depends on a "temperature" variable.  An "explanation" that does not describe the method nor explains the role of temperature is not an explanation of SA.
It is like saying "a horse is an animal with four legs". This sentence is surely readable, but it does not actually explains what a horse is; and will actually mislead the reader into thinking that any four-legged beast is a horse.
The text also implies that SA behaves like the greedy method, until it somehow detects that it has fallen into a local minimum; and only then takes some uphill moves.  Obviously this is not correct; SA will take uphill moves at any time, and cannot tell whether the current state is a local minimum.
Finall, the text is badly written:
*If P is a problem for which no better solution is known than an extensive brute-force search, then obviously SA cannot bebetter than brute-force!  
*Finding a set of 100 numbers that fit some characteristic is not a meaningful example: it may or may not require brute force and/or SA.
*that is the best solution for its current region: what is "its current region"?
*In an attempt to find a better solution, this technique may use various methods to jump out of the current pit: actually SA uses only one method, and uses it all the time.
*such as searching for better solutions randomly by a factor of the inverse amount of the previous adjustment: this sentence is hard to understand, but seems to be saying that the magnitude of an uphill jump depends on how big was the previous downhill jump.  This is false.
In conclusion, the "Plain English" section does not help the reader, and may even mislead him/her.
All the best, Jorge Stolfi 04:17, 18 October 2007 (UTC)
replies: text: Thanks for highlighting the issues with that section!  All the best, -- itistoday (Talk) 05:36, 2 November 2007 (UTC)
thread_title:  Plain English section 

message: Please dont include links to programs that claim to use SA unless there is some discussion on the target website of how the program specifically used the method, along with source code.  —Preceding unsigned comment added by 209.56.2.2 (talk) 19:35, 17 July 2008 (UTC)
thread_title:  On Links 

message: The text after the pseudocode listing is confusing. It seems to call into question the validity of the code without proposing a viable alternative. JKeck (talk) 15:11, 9 July 2014 (UTC)
thread_title:  What? Confusing text 

message: A procedure that is called now Simulated Annealing was developed by M. Pincus in 1970 who proposed to employ the Monte Carlo sampling based on Metropolis et al. algorithm (1953) to find the global minimum of a function of many variables.
A generalization of the statistical mechanics of a non-ideal gas by extending its application to non-physical multi-variant systems, which is not related to the Metropolis algorithm, was proposed by Khachaturyan et al ( 1979,1981). The authors introduced definitions of the non-physical thermodynamic functions, partition sum, free energy, temperature, and equilibrium densities as averages over the Gibbs ensemble of these systems.
That was done well before S. Kirkpatrick (1983,1985).
A number of users (including myself)  tried to edit the intro section of the paper, but all changes were reverted by a certain "MrOllie". My last change from Jan 21 2020 which mentioned re M.Pinkus paper from 1970 and independent reference to it  was reverted WITHOUT ANY EXPLANATION, by the same "MrOllie". When I complained about it to Wikipedia editors I received  the following
> > > However, since article content is not controlled by a central authority, we do not resolve editing disputes via email. In light of this, you have a few options:
> > > 1.) If you think there has been a simple misunderstanding, you might begin a discussion on the article's talk page to try to engage other editors and get a sense of what is happening with this article. You can do this by clicking on the "Talk" tab located along the top of the article and then clicking on the "New Section" tab on the following page. Be sure to give your new section a title (like, "Concerns over article content", etc.) and once you write down your concerns you should sign the entry with four tildes ~~~~ before clicking on Save. Then you should check back occasionally to see if anyone has responded. This may be the simplest way to handle your issue.
I was also advised about an option to revert "MrOllie" changes, but I was warned that I might be blocked, if I do it. ( I was surprised that "MrOllie" wasn't blocked for very same reason).
Following advise of Wikipedia editors. I am putting this issue into the talk page.
Any comments/advises ?
You can see changes related to Mr. Pincus and Prof. Khachaturyan in the history (Dec 2019 and Jan 2020). What's especially puzzling is that "MrOllie" reverted the changes nearly immediately, on one occasion within minutes. — Preceding unsigned comment added by SimulAnnT (talk • contribs) 
:If you want to give someone new credit for inventing this, you need secondary sources that explicitly say that. Without them, you are just engaging in original research, which we don't do on Wikipedia. - MrOllie (talk) 20:47, 3 June 2020 (UTC)
replies: text: Let's start simply: Which source, specifically, says that "A procedure that is called now Simulated Annealing was developed by M. Pincus in 1970"? - MrOllie (talk) 15:56, 5 June 2020 (UTC)

text: Yes, I read that. I don't see it stating anywhere that Simulated Annealing was developed by Pincus. Please be specific, which text exactly supports that claim? Quotes or page numbers, it is a long enough book that readers should not be made to hunt for this. - MrOllie (talk) 20:00, 12 June 2020 (UTC)

text: 'Pincus noticed the anaology' is not remotely the same thing as 'Pincus developed simulated annealing.' In fact, your source says the opposite elsewhere: "An algorithm that follows the fourth approach was independently introduced by Kirkpatrick et al and Černy. It is generally known as simulated annealing", as well as the quote highlighted by User:Joel B. Lewis in his edit summary "The result is the tool called "simulated annealing", which, since its inception in 1982." I think you misunderstand what the source is saying. Also, your new Carnes citation calls van Laarthoven and Aarts a "misapprehension of history". I don't think using both makes any sense. - MrOllie (talk) 00:23, 13 June 2020 (UTC)

text: That's not what *I* wrote, that is what *your source* wrote. We cannot go beyond what the sources say and substitute our own interpetations. The 'common feature' of my edits is to strictly follow what the sources actually say, not your overly generous interpretation of them. - MrOllie (talk) 12:06, 2 July 2020 (UTC)
thread_title: About invention of simulated annealing

message: User:SimulAnnT, the sources you introduced noted that this technique was independently arrived at by several authors. Your version obscures this and suggests that everyone was copying Pincus. We must follow the sources on this.
Even setting that aside, you are adding a large amount of text to the lead section. Per MOS:LEAD, the lead should be a short summary of the rest of the article and not contain unique information. - MrOllie (talk) 16:36, 19 August 2020 (UTC)
thread_title:  Independently described 

message: The article says "simulated annealing may be preferable to exact algorithms such as gradient descent or branch and bound". I didn't know what an exact algorithm is, but GPT-4 and google both indicate that it's one that finds the optimal solution given infinite time. Gradient Descent doesn't find the optimal solution given infinite time (will get stuck in a local optimum), so I don't get the sentence. Can someone explain? 2A02:8071:7141:6400:647B:F5D6:9075:304C (talk) 09:04, 2 April 2024 (UTC)
replies: text: Exact algorithm is not a term of art AFAIK and so your search isn't giving good results. A contrast is being made with non-statistical algorithms. Perhaps a better term would be Heuristic algorithm but I haven't checked to see if this is supported by reliable sources. ~Kvng (talk) 15:52, 9 April 2024 (UTC)
thread_title:  "Exact algorithm"