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#11
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Decreasing Errors For Binary Star System Masses
On Monday, October 27, 2014 3:21:53 AM UTC-4, Robert L. Oldershaw wrote:
[Mod. note: reformatted. I would characterize this whole thread as 'harping on trivial issues' given that either the whole dataset or the subset you arbitrarily chose rule out your preferred model at extremely high confidence levels. I am tempted to close it here unless there is anything more interesting to add. -- mjh] 1. I dispute your argument that the existing 49 data-point subset is sufficient to "rule out" my prediction. 2. While not statistically convincing yet the existing subset's mass distribution looks more like what I would predict than what you would predict. 3. Are you absolutely positive that when the subset reaches 200 data-points it will have shifted away from my predictions and verify your expectation? |
#12
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Decreasing Errors For Binary Star System Masses
I find the subject of radial velocity measurements fascinating so I
hope the moderator allows a couple of more comments. [Mod. note: new insights are always welcome: it's the rehashing of tired old argument that I am trying to avoid -- mjh] 1. The Southworth catalog includes stars of range 0.21 to 27 solar masses. The rotational broadening present in higher mass stars can limit the accuracy of the radial velocity determination and the sharpness of the eclipse. 2. The catalog includes stars with periods ranging from 0.8 to 771 days. The accuracy of the data improves as more eclipses are observed but this is more difficult with longer period orbits. These factors are taken into consideration when using the quoted error bars, and are *not* taken into account when selecting by publication date. On Monday, October 27, 2014 3:21:53 AM UTC-4, Robert L. Oldershaw wrote: I also said that at some point in the new millennium I noticed a marked and general improvement in stellar mass estimates. This is reflected in the decreased error values and the decrease in conflicting mass estimates by different research groups. No you did not notice this. 1. The newer data does not have smaller error values (see my previous plot). 2. The catalog gives only only mass estimate for each star, so how could you notice conflicting mass estimates? It seems that you are being dishonest. The choice of a start date of 2012 can be characterized as arbitrary, but most scientific tests based on observational data involves a choice of the data to be used in the test. Scientific tests do not use an arbitrary choice. I would hope a paper that only quoted results from left-handed astronomers would be rejected. Your criteria are barely better than this. since my explicitly chosen sample is an open-ended and growing sample, the choice of a 2012 start date is a trivial issue that becomes evermore trivial with time and sample growth. Yes, if we only select data from left-handed astronomers then we would eventually get the same results we would have gotten by not making this arbitrary selection. It just takes longer to collect sufficient data. --Wayne |
#13
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Decreasing Errors For Binary Star System Masses
In article ,
Robert L. Oldershaw wrote: 1. I dispute your argument that the existing 49 data-point subset is sufficient to "rule out" my prediction. It's not an argument: it's a fact. You can apply simple undergraduate-level statistical tests to the data to verify this for yourself. Or you can see the earlier discussion where I did it for you. The data are conclusively inconsistent with your model and they are consistent with being uniformly distributed within the mass range. 2. While not statistically convincing yet the existing subset's mass distribution looks more like what I would predict than what you would predict. No it doesn't: that's the whole point of the test. (I have never predicted anything, of course: I've simply tested the prediction that you provided and found it inconsistent with the data.) 3. Are you absolutely positive that when the subset reaches 200 data-points it will have shifted away from my predictions and verify your expectation? I don't have an expectation to be verified. What I can say is that, based on the data we now have, it would be absolutely astonishing if new data suddenly started to favour your model to the extent that the confidence levels of rejection on statistical tests started to make it viable again, 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 |
#14
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Decreasing Errors For Binary Star System Masses
On Tuesday, October 28, 2014 5:12:15 AM UTC-4, Martin Hardcastle wrote:
It's not an argument: it's a fact. You can apply simple undergraduate-level statistical tests to the data to verify this for yourself. Or you can see the earlier discussion where I did it for you. The data are conclusively inconsistent with your model and they are consistent with being uniformly distributed within the mass range. But they certainly do not prove that the distribution is uniform either. The first subsample of 34 binary star masses showed a clear preference for my predicted multiples and a very clear avoidance of the gap between the peaks. You attributed this to a statistical fluke and said that more data would lead to the uniform distribution you expect. The newer 14 member subsample has a similar distribution to the first 34 member subset. I suppose you will claim that this is another fluke. But here is the important question. If we get to 200 masses and the distribution still favors multiples of 0.145 solar mass and disfavors inter-peak masses, would this still be considered a fluke? In other words, is there *any* point at which you would think that maybe something scientifically interesting and unexpected has been identified? Or is it always a confederacy of flukes? [Mod. note: reformatted -- mjh] |
#15
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Decreasing Errors For Binary Star System Masses
On Tuesday, October 28, 2014 4:54:17 AM UTC-4, Robert L. Oldershaw wrote:
It is interesting and informative to apply your reasoning to the entire history of the research effort to determine the value of the Hubble constant. Precision is all well and good, but it is profoundly trumped by accuracy. Lately we have seen bold claims of 7-sigma detections go up in flames, or get buried by dust. Clearly statistics are a double-edged sword. Measuring the Hubble constant is extremely difficult. Measuring masses of eclipsing binaries is extremely easy. You slandered the eclipsing binary community when you said without providing evidence that there were eclipsing binary mass measurements that disagreed with each other. Could you please withdraw this statement or provide evidence for it? The eclipsing binary measurements are more analogous to measuring the brightness of stars. Ever since the development of linear detectors (CCDs), there is no reason to doubt the accuracy of stellar brightness measurements. The precision can improve, and one can now observed fainter stars, but it is ridiculous to bring up the subject of systematic errors for these simple measurements. Or perhaps you think that the pre-2012 researchers missed a factor of two when applying Kepler's law? --Wayne [Mod. note: reformatted -- mjh] |
#16
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Decreasing Errors For Binary Star System Masses
In article ,
Robert L. Oldershaw wrote: But they certainly do not prove that the distribution is uniform either. Why, no. I assume you're familiar enough with statistics to realise that 'consistent with X' and 'proves X' are different things. It's impossible in principle to prove uniformity to some arbitrarily low level with any given finite dataset. The first subsample of 34 binary star masses showed a clear preference for my predicted multiples No, you don't understand. It was consistent with being uniform. That means you cannot claim there were any 'clear preferences' for anything else. The null hypothesis has to be the uniform distribution. You attributed this to a statistical fluke and said that more data would lead to the uniform distribution you expect. I didn't make any claim about what more data would do, if I recall correctly, but certainly the most plausible hypothesis based on the existing data is that they will continue to be consistent with being uniform. The newer 14 member subsample has a similar distribution to the first 34 member subset. I suppose you will claim that this is another fluke. I won't claim anything until I or someone else has done an appropriate statistical test. Have you? But here is the important question. If we get to 200 masses and the distribution still favors multiples of 0.145 solar mass 'still' is of course not true: the data do no such thing. and disfavors inter-peak masses, would this still be considered a fluke? In other words, is there *any* point at which you would think that maybe something scientifically interesting and unexpected has been identified? Sure, that kind of goes with being a scientist: you have to believe what the data say. If a statistical test ever shows that those residuals are non-uniform to a high confidence level, I will be as interested and surprised as anyone else. But I will accept no substitute for a high-confidence result on a standard statistical test based on an appropriately selected sample: certainly not statistically naive handwaving about small cherry-picked samples. Since tests on the existing Southworth catalogue or any sensibly selected subset of it show no significant deviations from uniformity, I see no reason to expect that that's going to happen. Meanwhile, let's ask the opposite question. Supposing the data are completely inconsistent with quantization -- and, so far, they are -- what will you do? Is there any observation that would modify *your* beliefs? Are you willing to commit to some action once we have some specified number of observations, and abide by it? (That would have the advantage that we could hope to lay this topic to rest until the data were taken.) 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 |
#17
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Decreasing Errors For Binary Star System Masses
On Wednesday, October 29, 2014 6:55:34 AM UTC-4, Martin Hardcastle wrote:
Meanwhile, let's ask the opposite question. Supposing the data are completely inconsistent with quantization -- and, so far, they are -- what will you do? Is there any observation that would modify *your* beliefs? Are you willing to commit to some action once we have some specified number of observations, and abide by it? (That would have the advantage that we could hope to lay this topic to rest until the data were taken.) Bottom line first: I am willing to admit I am wrong about the M1+M2 stellar mass distributions for detached binary star systems if no preference is shown for the predicted preferred masses. Here is the current situation as I see it. No one else is required to see it this way. I make a simple histogram of deviations from the predicted peaks with 3 equally sized bins. For the 49 system set there are 24 systems closest to the peak, 5 systems in the inter-peak bin and 20 systems in the intermediate bin. This distribution was found for the 34 member set and the newer 14 member set. These results encourage me to think that when 3 more 50 member subsets are available, each subset might repeat the same pattern and the full 200 member set of systems would show a clear preference for the predicted peaks at n(0.145 solar mass). I repeat that others may reject this strategy, but it is the only one I can fully trust at the present time. [Mod. note: reformatted -- mjh] |
#18
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Decreasing Errors For Binary Star System Masses
In article , Martin Hardcastle
writes: Meanwhile, let's ask the opposite question. Supposing the data are completely inconsistent with quantization -- and, so far, they are -- what will you do? Is there any observation that would modify *your* beliefs? Are you willing to commit to some action once we have some specified number of observations, and abide by it? (That would have the advantage that we could hope to lay this topic to rest until the data were taken.) Probably not, as a "definitive prediction" (direct quote from the abstract) of a DSR paper has, now that experimental accuracy and precision is much better than when the paper was written, been falsified. There is no evidence of substructure of the electron at the predicted level. Measurements at DESY and elsewhere testing QED at small scales and assuming point-like fermions are completely consistent with theory. Any deviation would have been seen. |
#19
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Decreasing Errors For Binary Star System Masses
In article , "Robert L.
Oldershaw" writes: I make a simple histogram of deviations from the predicted peaks with 3 equally sized bins. Why 3? For the 49 system set there are 24 systems closest to the peak, 5 systems in the inter-peak bin and 20 systems in the intermediate bin. You once posted an example with more details. IIRC the widths of the bins were such that it was most likely to get a spurious signal. 0.145 is quite small; any reasonable stellar mass will be close to SOME multiple of it. This distribution was found for the 34 member set and the newer 14 member set. These results encourage me to think that when 3 more 50 member subsets are available, each subset might repeat the same pattern and the full 200 member set of systems would show a clear preference for the predicted peaks at n(0.145 solar mass). If I flip a coin 3 times and it comes up heads three times, I am not going to bet much on it coming up heads 10 times in a row. |
#20
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Decreasing Errors For Binary Star System Masses
In article ,
Robert L. Oldershaw wrote: Bottom line first: I am willing to admit I am wrong about the M1+M2 stellar mass distributions for detached binary star systems if no preference is shown for the predicted preferred masses. Excellent, because no statistically significant preference is currently shown in the full Southworth dataset or any subset of it, including the one you've chosen (quite arbitrarily, as Wayne has made clear elsewhere in the thread). This distribution was found for the 34 member set and the newer 14 member set. These results encourage me to think that when 3 more 50 member subsets are available, each subset might repeat the same pattern and the full 200 member set of systems would show a clear preference for the predicted peaks at n(0.145 solar mass). They may encourage you to think that, but they should not. In fact, as you were shown in several different ways last time this came up, the data for your 34-member subsample are consistent with a uniform distribution and so you have no grounds for believing anything else. As the late John McCarthy used to say, he who refuses to do arithmetic is doomed to talk nonsense. Or, to put it another way, if you want to convince anyone of anything in science, you need to learn to understand what is statistically significant and what isn't. I see we are pretty much repeating arguments from 9 months ago here. If there are no further new points to make then perhaps this thread should be closed at this point. 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 |
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