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#51
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Southworth Det Eclips Binary Catalog
On Thursday, December 5, 2013 1:51:20 AM UTC-5, wlandsman wrote:
winds observed in the spectra of red giants. The discrete self-similar paradigm can't address these questions because it has thrown out the physics and is built on only metaphor. (I would however be interested in learning how the paradigm is supposed to account for the high mass loss rates seen in red giant stars.) It is false and pejorative to say that Discrete Scale Relativity is "built on only metaphor". The discrete self-similar paradigm is based on a very large amount of empirical data from the subatomic to the galactic scales, AND it is built on discrete conformal invariance/symmetry (a topic that fascinated Weyl and Dirac, I might add). Your comment shows that you have not taken a serious idea seriously. When a highly excited atom makes a transition to a lower energy state, or more appropriately here, undergoes an ionization event leaving an ionic core in a low energy state, it loses mass/energy. Right? See any possible connection with a red giant blowing off its outer layers and a white dwarf being left behind? [Mod. note: that's *precisely* the sort of metaphor that the OP was talking about -- mjh] http://www3.amherst.edu/~rloldershaw Discrete Scale Relativity/Fractal Cosmology Robert L. Oldershaw |
#52
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Southworth Det Eclips Binary Catalog
In article , "Robert L.
Oldershaw" writes: (1) Using induction and pattern recognition I search empirical knowledge for unforeseen patterns and correlations. (3) Then the predictions and subsequently observed results can be compared at face value. You would say it does not matter until the statistical significance reaches a certain level. I do not agree. Note that it is well documented that humans see many patterns where none really exist. This has an obvious evolutionary explanation: it is better to have a false positive (think something is significant when it is not) than a false negative (think something doesn't matter when it does). There is a huge literature on this topic. This is how Democritus could learn so much about nature without any statistics or computers or advanced observational equipment. He was right about so many very fundamental things that saying he just made lucky guesses is not an acceptable answer. Note that there is a selection effect here. If many people make guesses, most will be wrong (and much Ancient Greek science was wrong), but some will be right. Some of those who were right were right just due to chance. |
#53
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Southworth Det Eclips Binary Catalog
On Friday, December 6, 2013 3:10:14 AM UTC-5, Robert L. Oldershaw wrote:
[Mod. note: Jonathan's suggestion would take about 5 minutes to implement with the current large dataset -- why not try it? -- mjh] ---------------------------------- Looked up CDFs and K-S test. Spent 5 minutes. Generated more questions than I started with. Will pay teacher/coach when time is propitious (we have plenty here). Time more important than money to me in this case. And when I release a paper on this subject into the public domain I would like it to be relatively "bullet-proof" because it will need to be, as has been so clearly shown at SAR. |
#54
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Southworth Det Eclips Binary Catalog
On Friday, December 6, 2013 1:30:23 PM UTC-5, Robert L. Oldershaw wrote:
[Mod. note: that's *precisely* the sort of metaphor that the OP was talking about -- mjh] There is a very large and scientifically important difference between "metaphor" and self-similarity. "*precisely*"? Where has our statistical precision and accuracy gone now? [Mod. note: quoted text trimmed -- mjh] |
#55
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Southworth Det Eclips Binary Catalog
In article ,
Robert L. Oldershaw wrote: On Friday, December 6, 2013 6:14:45 AM UTC-5, Martin Hardcastle wrote: Sorry, does that mean that you don't have a prediction for the intrinsic scatter about zero -- which makes your model untestable, since the scatter could in principle be much larger than 0.145 solar -- or that you aren't prepared to tell us what it is? --------------------------- The former is the current situation. I think we would need more empirical guidance before inducting a theoretical explanation. In the case of the Solar System (Tech Note #1 at my website) the delta M is about 0.003 solar mass. In the case of binary star systems the delta M can be much larger, say 0.01 to 0.04 solar mass. I made the assumption that the delta M is the maximum you quote, 0.04 Then to give the model the maximum possible credit I assume that any data point with |Q|0.04 contributes zero to the chi^2 sum (this is equivalent to assuming that the distribution is uniform in the range -0.04--0.04 -- in reality it would be peaked, which would give worse results, but since you can't tell us the shape of the distribution, I have to take the one that most favours the model). Then I take all the values of |Q|0.04, subtract 0.04, and find chi^2, for the full dataset we discussed earlier. The result? The model is still ruled out at the 99.99[x18] per cent confidence level. You can only save it if you make the intrinsic scatter so broad that it will be impossible to see any signal. Actually this is the way I personally test the merit of scientific ideas. (1) Using induction and pattern recognition I search empirical knowledge for unforeseen patterns and correlations. (2) The perceived pattern can be extended into the unknown (one's personal unknown, or much better, everybody's unknown) so as to make predictions. (3) Then the predictions and subsequently observed results can be compared at face value. You would say it does not matter until the statistical significance reaches a certain level. I do not agree. I use simple yes/no tests. No single test is sufficient in this method to prove the theory. BUT, if a theory can consistently pass these yes/no tests, especially if previous theories stumble on these results, then my confidence in that theory grows. If this method violates your statistical approach or your logic, then I would say that your statistics and logic are wrong. Straw man. Of course it's possible to have a yes/no test. For example, the answer to the question 'does your model describe the mass distributions of real stellar systems' is unambiguously 'no'. And, of course, knowing when this is the case and when it isn't often requires some knowledge of statistics. Not always, but often. I think that's all I have to say on the matter. Martin -- Martin Hardcastle School of Physics, Astronomy and Mathematics, University of Hertfordshire, UK Please replace the xxx.xxx.xxx in the header with herts.ac.uk to mail me |
#56
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Southworth Det Eclips Binary Catalog
On Saturday, December 7, 2013 3:40:46 AM UTC-5, Phillip Helbig---undress to reply wrote:
Note that there is a selection effect here. If many people make guesses, most will be wrong (and much Ancient Greek science was wrong), but some will be right. Some of those who were right were right just due to chance. ------------------------------------------------------- I got interested in Democritus in the 1990s and read the definitive source by Cyril Bailey, The Atomists... Oxford UP, 1928. I wrote a paper that was published in 1998 on Democritus. Democritus discovered/taught the following things about nature. - Atomic basis of matter (actually more like molecular, but...) - idea of vacuum between atoms - constant motion of atoms - basic concept of mass/energy conservation - basic theory of colors (primary and secondary) - constant formation and destruction of systems on macroscopic scales - Milky Way composed of stars - Sun is a star - heliocentric Solar System - light is composed of corporeal emanations from surfaces - basic ideas of perception - inherent limitations of observations Not too shabby for 2500 years ago. Too bad the Aristotelians and Platonists stopped this progress and led us into the Dark Ages for many centuries, until the Renaissance scientists rediscovered the wisdom of the Democritus and other ancient Greek scientists and got the ball rolling again. "Chance" is a ludicrous explanation in the case of Democritus. [Mod. note: we seem to be wandering away from research in astronomy and astrophysics -- mjh] |
#57
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Southworth Det Eclips Binary Catalog
On Saturday, December 7, 2013 3:47:10 AM UTC-5, Martin Hardcastle wrote:
The result? The model is still ruled out at the 99.99[x18] per cent confidence level. You can only save it if you make the intrinsic scatter so broad that it will be impossible to see any signal. I need a clarification on one point. First, forget about any intrinsic physical variability of stellar masses, for this question. If we had a sample of 100 binary systems and their total masses were all known to =/ +/- 0.03 solar mass. As a thought experiment, when we compare them to multiples of 0.145 solar mass, say *hypothetically* we find that 80 have deviations of =/ 0.02 solar mass, while 14 have deviations in the 0.21 to 0.04 solar mass, and 6 have deviations of 0.41 to 0.07 solar mass. Is there any chance that your preferred chi-squared test would indicate that this was a non-uniform distribution? Likewise would it possibly indicate that the distribution favors the preferred DSR masses over a random result. Or is the model still ruled out with high (low) probability. I don't need an answer based on a full analysis, just an informed guess would do. I want to get an intuitive feeling for what properties a sample would have to have in order to support my model. |
#58
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Southworth Det Eclips Binary Catalog
On 12/8/2013 9:24 AM, Robert L. Oldershaw wrote:
On Saturday, December 7, 2013 3:47:10 AM UTC-5, Martin Hardcastle wrote: The result? The model is still ruled out at the 99.99[x18] per cent confidence level. You can only save it if you make the intrinsic scatter so broad that it will be impossible to see any signal. I need a clarification on one point. First, forget about any intrinsic physical variability of stellar masses, for this question. If we had a sample of 100 binary systems and their total masses were all known to =/ +/- 0.03 solar mass. As a thought experiment, when we compare them to multiples of 0.145 solar mass, say *hypothetically* we find that 80 have deviations of =/ 0.02 solar mass, while 14 have deviations in the 0.21 to 0.04 solar mass, 0.21 can never happen. They can only have deviations up to 0.0725 solar mass if you compare them to the nearest multiple of 0.145 (and if you don't take the nearest then it's not clear which one you *are* taking). ... and 6 have deviations of 0.41 to 0.07 solar mass. Likewise, this interval is almost completely outside the range of attainable outcomes! In addition it is overlapping the previous range you gave (0.04 to 0.21) so you are using overlapping bins, which would make your question ill-defined. Maybe you miscalculated the example values, but in this way it is completely unclear what the question actually is. -- Jos [Mod. note: I would assume he means 0.021 to 0.040, 0.041 to 0.07 -- mjh] |
#59
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Southworth Det Eclips Binary Catalog
In article ,
Robert L. Oldershaw wrote: First, forget about any intrinsic physical variability of stellar masses, for this question. If we had a sample of 100 binary systems and their total masses were all known to =/ +/- 0.03 solar mass. As a thought experiment, when we compare them to multiples of 0.145 solar mass, say *hypothetically* we find that 80 have deviations of =/ 0.02 solar mass, while 14 have deviations in the 0.21 to 0.04 solar mass, and 6 have deviations of 0.41 to 0.07 solar mass. Is there any chance that your preferred chi-squared test would indicate that this was a non-uniform distribution? The chi^2 test is checking for consistency with the model, not a non-uniform distribution. Calculating the chi^2 statistic is easy: add up the squares of the ratios of the deviation from the model prediction to the error bar. So in this case, I'll assume that the deviations are all in the middle of your range and that the error bars are all 0.03, and then we have chi^2 = 80*(0.01/0.03)^2 + 14*(0.03/0.03)^2 + 6*(0.055/0.03)^2 This would give a chi^2 of 43 for 100 degrees of freedom, which (you can check this on an online calculator) would very definitely be consistent with your model. (However, it would also be literally too good to be true -- the typical deviation from the model prediction for most objects is significantly less than the error bars, which in real data would be a sign either that the error bars were wrong or that someone was cooking the books.) If instead the errors were all 0.01, say, then instead we would have a chi^2 of 388 and the model would be ruled out at a very high confidence level. This is why the errors matter. Martin -- Martin Hardcastle School of Physics, Astronomy and Mathematics, University of Hertfordshire, UK Please replace the xxx.xxx.xxx in the header with herts.ac.uk to mail me |
#60
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Southworth Det Eclips Binary Catalog
On Monday, December 9, 2013 3:51:13 AM UTC-5, Martin Hardcastle wrote:
[stuff] Many thanks for this post. Long ago and far away (Seattle) as an oceanography/chemistry student I took a course in statistics and actually learned how to do chi-squared tests, among other things. Thanks to your post I have the motivation to pull out my old statistics text and relearn how to do this basic stuff. Statistics is like a foreign language that I once had a working knowledge of but that I forgot due to lack of use. My only excuse is that I needed time and brain-space for other pursuits that involved a very different set of discovery and evaluation tools. I heartily agree that errors matter, especially systematic errors that, when combined with high precision, can give the false impression of virtually "final" answers. One thinks here of the ongoing proton radius issue. Precision appears to be fairly straightforward to determine. Accuracy is a much more difficult thing to determine. [Mod. note: reformatted -- mjh] |
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