What is a Theory?

I guess "accuracy" tends to mean precision, exactness, correctness, exactitude. Science is generally running after this. Ambiguity can come from the opposition between two different interpretations of an observation, and also from the potential complexity of the subject being studied.

olivortex writes:

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I guess "accuracy" tends to mean precision, exactness, correctness, exactitude.

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To be pedantic: Not quite. There is a big difference between "accurate" and "precise."A "precise" measurement will have a lot of significant digits. An "accurate" measurement will have whatever significant digits it has being correct.Numbers can be accurate, but not very precise ("3" as the value of pi) and similarly, precise, but not very accurate ("2.71828182845904523536" as the value of pi).That's one of the ways that you can tell when someone is trying to snow you: Their numbers are extremely precise. They don't have "25%" but rather "24.739%" Really? You were able to measure it that precisely? Your apparatus is capable of providing that level of detail such that you can carry five significant figures?The goal, of course, is to get both accurate and precise data.Edited by Rrhain, : Better definition of "accurate"

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Rrhain

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Thank you for your submission to Science. Your paper was reviewed by a jury of seventh graders so that they could look for balance and to allow them to make up their own minds. We are sorry to say that they found your paper "bogus," specifically describing the section on the laboratory work "boring." We regret that we will be unable to publish your work at this time.

Thanks for your PRECISION I guess my understanding of english will improve thanks to people like you, on this forum. Sometimes it gets way too technical for me, but it can't be useless!It is true that accurate is not necessarily precise and vice versa. It's a bit like the quality/quantity relationship. By the way i must eat something not too big but good before i go to sleep.See you!olivortex | Listen and Stream Free Music, Albums, New Releases, Photos, Videos

Not to be nitpicky but: The number you gave is the value of ewhich curiously enough rounds to 3 at one place accuracy thus pi = e to zero decimal places.Edited by bluescat48, : italic

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There is no better love between 2 people than mutual respect for each other WT Young, 2002Who gave anyone the authority to call me an authority on anything. WT Young, 1969

Yep, that was Rrhain's point - it is a very precise value to give as an answer to the question, "what is Pi?", but it is not at all accurate.

One of my favourite textbook illustrations was about these ideas. It showed a target with a duck drawn in the middle and various results of shotgun blasts. Closely-spaced groupings were precise, but only those on the centre were accurate. One showed hits all over the place, with none hitting the duck, and was labelled "On average, the duck was dead.".

Actually similar to Woodsey's duckhunt analogy, in military applications i.e. Naval Gun Fire Support (firing a 5" projectile 3 miles away to take out enemy suppression fire in support of U.S. Marine movement on a beach head), precision and accuracy are very different but related concepts as shown here: However, what you want in both military and scientific applications is to be both accurate and precise. That usually gives the best results.Edited by DevilsAdvocate, : No reason given.

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For me, it is far better to grasp the Universe as it really is than to persist in delusion, however satisfying and reassuring.
Dr. Carl Sagan

bluescat48 responds to me:

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The number you gave is the value of e

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How nice to see somebody who knows that. Some people memorized pi. I memorized e. Pi is a button on my calculator, but e is not (I have since acquired a better calculator.) You can get it from using the "e^x" function, but not all calculators can do that so it was just easier to memorize the digits.Indeed, to one significant figure, an "accurate" measurement of both pi and e would be "3." But "3" isn't a very "precise" measurement of either. "3.00000" is extremely precise (because all those zeroes after the decimal point are significant), but it isn't very accurate with regard to pi or e.eⁱ + 1 = 0Because of that, all of reality follows.

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Rrhain

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Thank you for your submission to Science. Your paper was reviewed by a jury of seventh graders so that they could look for balance and to allow them to make up their own minds. We are sorry to say that they found your paper "bogus," specifically describing the section on the laboratory work "boring." We regret that we will be unable to publish your work at this time.

Message contents should have some explicit connection to the question "What is a Theory?".Adminnemooseus