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Wikipedia: accuracy and potential


Mr Skeptic

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Dr. House: What's wrong with you?

Little Girl: I got spinal muscular atrophy.

Dr. House: At least it's not contagious. Nice bear.

Little Girl: It's a dog.

Dr. House: It's a bear.

Little Girl: His name is Bill. He's a dog.

Dr. House: Words have set meanings for a reason. If you see an animal like Bill and you try to play fetch, Bill's going to eat you, because Bill's a bear.

Little Girl: Bill has fur, four legs, and a collar. He's a dog.

Dr. House: You see, that's what's called a faulty syllogism; just because you call Bill a dog doesn't mean that he is... a dog.

 

 

 

 

Fred, am I going to have to lay the entropy smack-down again?

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Entropy: is change. Thermodynamic entropy is a change in heat in some system, or part of a (closed) system.

 

Heat isn't a property, it's a process, and we've covered that ground before. Entropy change is Q/T, the amount of heat divided by the temperature.

 

Entropy change is certainly enabled in chemistry by the motional energy of molecules (that can be can be increased by bond energy change in chemical reactions) but thermodynamic entropy is only actualized if the process itself (expansion, heating, mixing) makes accessible a larger number of microstates, a maximal Boltzmann probability at the specific temperature. Information ‘entropy' only has the latter factor of probability

 

Those links you think I should read: can you paste anything from that refutes the statement: Entropy = change ?

 

"Entropy serves as a measure of the number of quantum states accessible to a macroscopyic system at a given energy." No mention of change there.

 

If entropy is change, why does it say "entropy change" at the beginning of the earlier statement?

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I think Wikipedia is fine for rather basic things. So if you want to find out the date of the battle of Nasby, then wikipedia is quite good.

 

It is not very good with advanced or controversial topics, mainly because either there is not an 'accepted' viewpoint or the topic is beyond the scope of the guy who wrote the article. So a lot of the particle physics info is just wrong, or perhaps 'misinterpreted' would be a better word.

 

Also, ironically, it is a lot less speculative than scientific journals. Anything the wiki big-wigs don't like gets instantly deleted. This tends to be anything in variance with the traditional viewpoint, and the big-wigs tend not to know enough about the subject they review to tell a good new idea from a crackpot one.

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Those links you think I should read: can you paste anything from that refutes the statement: Entropy = change ?

 

"Entropy serves as a measure of the number of quantum states accessible to a macroscopyic system at a given energy." No mention of change there.

 

If entropy is change' date=' why does it say "entropy change" at the beginning of the earlier statement?[/quote']

Your 'methods' OK to keep thumping this one around?

“energy” in entropy considerations refers to the motional energy of molecules' date=' and (if applicable) any phase [b']change[/b], and (in chemical reactions) bond energies in a system.

 

“dispersal of energy” in macro thermodynamics occurs in two ways:

 

(1) "how much" involves heat transfer, usually ΔH, to or from system and thus from or to its surroundings;

 

(2) "how widely" means spreading out the initial energy of a system in some manner, e.g., in gas expansion into a vacuum or mixing of ideal gases, the system's volume increases and thereby the initial energy of any component is simply more dispersed in that larger three-dimensional volume without any change in motional or other energies.

 

In chemical reactions, ΔG is the function that must be used to evaluate the net energy dispersal in the universe of system and surroundings.

 

In macro thermodynamics, both spontaneous and non-spontaneous processes are ultimately measured by their relationship to ΔS = qrev/T, where q is the energy that is dispersible/dispersed.

The pitfall is to think or say that ΔS_system is "the entropy" change. It's not since it is only part of the total entropy change.
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So let me see if I've got this right: if "change" appears anywhere in an explanation, you see this as support for "entropy = change"

 

Got it.

 

You, of course, didn't notice the context of what was written; one of the passages was "without any change." It's one thing to read the words, but another thing to understand what they mean when you string them together.

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"When we use a word, it means exactly what we say it does!"
entropy means what scientists say it means

What's a scientist?

No-one who disagrees with entropy = change can claim to be one' date=' can they?

They might be people who understand enough to hold some job down,

but someone who says it's [b']wrong [/b]to say "Entropy and change are the same" can't be very educated about what entropy is. IMO.

But then I'm not a scientist like you guys.

Now tell me I'm all wrong, go on.

as support for "entropy = change"...

I present everything I've posted in this and other threads on the topic, only. And any 'discussions' with you 'scientists' about it, which never seem to come to any conclusion.

one of the passages was "without any change"
What do you think this refers to? What does dispersal without change suggest?
Got it
Really?
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What's a scientist?

 

Well... since you've AGAIN edited your post after the fact, I will reply again.

 

No-one who disagrees with entropy = change can claim to be one, can they?

They might be people who understand enough to hold some job down,

but someone who says it's wrong to say "Entropy and change are the same" can't be very educated about what entropy is. IMO.

But then I'm not a scientist like you guys.

Now tell me I'm all wrong, go on.

Okay, besides your ad hominem attack and false dichotomy, you are wrong.

 

You said explicity that entropy = change.

If this logic is accurate, this means also explicitly that change = entropy.

This is due to the understanding that equality is reflexive, symmetric, and transitive.

Equality implies equivalence.

 

 

To prove your assertion wrong, one simply must come up with an example of change that is not entropy, since your calling them equal implies their equivalence.

 

 

 

Anyone wish to offer any examples to FRED (troll that he is) of a change that is not entropy?

 

 

Be sure to differentiate between closed systems and overall universe, because (troll that he is) Fred will play semantic games with you to pretend you're wrong even when your example is understood in context by 99% of all readers.

 

 

 

 

Have you got something stuck?

Troll.

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...the entropy of any wiki, or node. It's a library where the books aren't static copies. There's a record, or audit, of changes. Entropy = change, so higher entropy is a measure of how contentious any article is. Expectation comes into it too, or uncertainty[/b'].
Like I said, and I'm right (coz I know)

 

To prove your assertion wrong' date=' one simply must come up with an example of change that is not entropy. Anyone wish to offer any examples...of a change that is not entropy?

[/quote']Come on then, Mr I now it all.

I bet you can't, there's no such thing, for a kick-off.

 

all expenditure of energy (including that made to find and ingest food), therefore represents the entropy[/b'] of the acquired learning (knowledge or information). In other words all observers are the result of their entire lifetime of 'observation'.

I reckon so.

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Troll.

 

I know truth is a defense, but degenerating into this only invites back-and-forth sniping and just drags things lower, so please refrain from this (please note that this is directed at any and all who are tempted to engage in baiting while trollspotting).

 

The situation been addressed. Move along. We bring you back to your regular discussion.

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Back to the topic at hand ...

 

I think Wikipedia is fine for rather basic things. So if you want to find out the date of the battle of Nasby, then wikipedia is quite good.

 

I would go a bit beyond basic. Wikipedia borders on excellent in most academic subjects up to the sophomore college level, and does a very good job up to the senior college level in many topics.

 

It is not very good with advanced or controversial topics ...

And this is where the problems lie. All it takes are a few pschoceramicists who in some twisted view think defacing the knowledge laid down by Einstein or Darwin or Freud or (name your luminary) proves their worth. Apparently the wiki big-wigs have clamped down on this problem to some extent. I see a lot less pyschoceramics in wikipedia now than in its early days.

 

Also, ironically, it is a lot less speculative than scientific journals.

 

Nothing wrong with this, per se. I don't go to an encyclopedia when I want to find recent research on some topic. If I want to see what is current (that is, a year old or so) I look at recent conference proceedings. If I want to see the cutting edge I look at arxiv. Even scientific journals tend to be a bit staid and out-of-date given the tough peer review and the long time span between submission and publication.

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I am a total wikipedia person. I love wikipedia. Inaccuracies are minor compared to the wealth of knowledge. Heated politicala nd social issues are going to be just as accurate on wikipedia as any where else...you'll get someones bias. But wikipedia for basic chem info or info on a single subject is great.

 

Chemkid

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It seems wikipedia is launching a search engine, which would make it a competitor to google. At the moment, they seem to have an alliance, with wikipedia very frequently showing up as the top google search result for most subjects. Might this change anything? Links:

http://technology.newscientist.com/article/mg19626345.500-wikipedia-founders-google-rival-to-launch.html

 

From http://en.wikipedia.org/wiki/Wikia#Search_Wikia:

On 31 January 2007, at a talk given at New York University, Wales announced that Wikia plans to build a search engine rivaling those of Google and Yahoo based on the kind of collaborative cooperation which has been so successful in developing Wikipedia, arguing that "search should be open, transparent, participatory, and democratic."[16] He later suggested this new approach could account for five percent of the search market

 

It occurs to me that if they gain control of internet searching, they will be insanely powerful (and will increase their rate of growth.)

 

On the other hand, google might be competing with wikipedia as well

knol is a project planned by Google for user-generated articles on topics ranging from "scientific concepts, to medical information, from geographical and historical, to entertainment, from product information, to how-to-fix-it instructions."[3] It was announced on December 13, 2007. knol pages are "meant to be the first thing someone who searches for this topic for the first time will want to read", according to Udi Manber, a Vice President of Engineering at Google.[3] The term knol, coined by Google to mean a "unit of knowledge"[4], refers to both the project and an article in the project.[3'] The site has been seen by many as Google's attempt to compete with Wikipedia, while others liken it to About.com.[5]

 

Whatever happens, this may be an interesting turn of events in the web world.

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It seems the competition works in both directions:

 

 

http://news.yahoo.com/s/nf/20071217/tc_nf/57269

Google is developing an online publishing system that many are saying could rival Wikipedia. Google's system will display content penned by folks who have knowledge about various subjects.

 

Google is calling the project "knol," which the company says stands for a unit of knowledge. Currently in the invitation-only beta stage, knol will allow people to develop Web pages oriented on a broad range of topics.

 

"There are millions of people who possess useful knowledge that they would love to share, and there are billions of people who can benefit from it. We believe that many do not share that knowledge today simply because it is not easy enough to do that," wrote Udi Manber, Google's vice president of engineering, on the official Google blog.

 

 

 

ABC News story by video:

http://video.google.com/videoplay?docid=-3163042687126374787&q=knol+news&total=1&start=0&num=30&so=0&type=search&plindex=0

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What do people think of the accuracy of Wikipedia in science related articles?

 

I have been impressed with the depth and clarity of several science articles on Wikipedia. Jimmy Wales, the founder of Wikipedia, has been making an effort these last few years to recruit professionals in scientific fields to write Wikipedia science entries, and it shows. It is unfortunate that much of the rest of Wikipedia is not so well written.

 

On a related note, what do people think the potential of Wikipedia is? Will its accuracy continuously increase, or will vandals and incompetents keep it low? Will Wikipedia become the ultimate dictionary of the future/repository of knowledge, or is it the predecessor of the Hichhicker's Guide to the Galaxy version 0.001 (the guide, not the book)?

 

I think of Wikipedia as a big notebook, and all the contributors are like students in a huge class taking notes in the notebook. In every class of decent size there will be those who are very good note takers, and those who just doodle on the pages. Wikipedia combines all of these different styles and qualities into one source.

 

Will wikibooks replace textbooks?

I don't believe that would be appropriate. As long as you think of Wikipedia as a collection of class notes on a subject, you are ok, but you should not accept it as authoritative. It's just notes.

 

BTW, I am a Wikipedia contributor. I have edited scores of pages over the last few years.

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Wiki accuracy! Well so far I have nothing to complain! I mean, doubting in the accuracy of Wiki it's like asking Einstein "what is the result of 2+5" and doubting his answer!

 

Yeah, Einstein might think you are silly and tell you the answer is 6, right?

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