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Originally Posted by dgruss23
Either you did not read Bell’s paper carefully when you made the above claims or … well its better to just assume you didn’t read his paper carefully. Starting with your first Bell quote it is important to go back and add in the full statement that you snipped so that there is proper context:
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See my note to Nereid above: I missed that part of the paragraph when skimming the paper, and already admitted that fact. But Nereid makes the point that my comment is still valid, though in a different way. And Bell has a history of not understanding the data he uses: see my comment
in this BAUT thread about his complete misunderstanding of the SDSS selection function.
I did not do a thorough reading of the paper. But it did not take a detailed reading to determine that it was a rather typical intrinsic redshift paper, in that the author did not understand the catalog that he used to draw his conclusions from. For something like this, definitions are vitally important.
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Originally Posted by dgruss23
In addition, Bell was specifically saying that while the VCV contains SDSS quasars, Seyferts, and BLLacs, it is uncertain how many AGN galaxies from the SDSS survey are in the VCV - and he gives a reason. The color selection technique is biased against detecting AGN galaxies with low luminosity nuclei.
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It still means that Bell doesn't understand the catalog. I'd love to see Bell define the distinction between "Seyferts", "SDSS quasars" and "AGN galaxies from the SDSS."
Heck, I'd love to hear him define "AGN galaxy."
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Originally Posted by dgruss23
His argument was that we can be pretty sure that the AGN listed in the VCV are AGN as opposed to non-AGN. Was his argument correct? If not, or if not that simple, then in order to be a relevant argument against the content of his paper you would need to adopt the position that a significant portion of the VCV catalog objects listed as QSO’s and AGN are objects that may not actually be AGN – and therefore could potentially impact Figure 2 of his paper. Is that the position you’re taking? It’s your supposed strike, so it’s a very relevant question.
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As I said, I'm not familiar enough with VCV (and cannot directly access A&A, though I'm trying to get a copy of the paper) to know the details of their catalog. Knowing what I do about the authors, I trust that their contamination fraction (from non-active sources) is low. But Bell gives no reasons to believe that is the case, besides his comment that it is easy to distinguish AGN from non-AGN. As I said, that is true for some classes of AGN, and some types of observations. Bell provides no reasons to trust that VCV contains only those sources that are easy to distinguish.
Keep in mind, that it is also very important to understand which AGN are missing from VCV, as that can have a very important impact on Bell's claims. He says nothing about this. I took his comment to read both ways: since they are easy to distinguish, VCV should be both low in contamination (it probably is) and complete (it probably isn't). I am aware of the context of his statement (only with regards to contamination), but he says little of value about completeness.
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Originally Posted by dgruss23
Do said papers present anything that makes it likely that the sample of QSO’s and AGN in the VCV are contaminated by a large portion of non-AGN?
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Not necessarily, but there are always posters about new methods of finding AGN. Bell's comment suggested that he believed AGN and "other types" (whatever that means) of galaxies are easy to distinguish. Sometimes yes, sometimes no. The onus is on him to convince us that VCV contains the easy ones, or was careful enough in excluding others. Even just a quote from their paper about their selection methods would suffice.
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Originally Posted by dgruss23
It is really not very good to have your critique contradicted by the very same sentence upon which you base your critique.
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Again, I already admitted I'd missed that. It's rather embarrassing, but it happens. Need I grovel upon the floor?
I was not a reviewer for the paper, did not read it particularly carefully (I was too busy exploding over various bits of nonsense) nor do I particularly care about the results of it: I am already on record (see the link above, if not elsewhere) as stating that the intrinsic redshift crowd is essentially irrelevant in modern astronomy. This paper does nothing to assuage me of that notion.
If you have evidence to the contrary, I'd love to see it.
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Originally Posted by dgruss23
Then you make the error of suggesting a strike (and presumably basis for rejecting the paper) that you fail to justify with specifics. Implicit in the way you have made your arguments appears to be a notion that any debatable statement is grounds for immediate rejection of the paper. How about this – when the referee report is written, the referee asks the author to clarify or put some qualifiers on that sentence about AGN being easy to distinguish from other galaxies? Or … if the reviewer thinks that - contrary to what Bell was actually arguing - the VCVcat could be contaminated by a large sample of non-AGN, the reviewer ask Bell to go through the VCV sample and verify the objects are AGN – culminating in a re-plot of Fig. 2 after eliminating any contaminating non-AGN galaxies.
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All of those are great suggestions. But as I said, I wasn't the referee, and I'm not refereeing it now, just pointing out some stupid things in it that make me think the whole thing is suspect. If you want to go and check on those points, feel free, but I certainly won't.
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Originally Posted by dgruss23
But rather than suggest improvements to the paper, you just throw out the whole paper based upon a flaw that you’ve not demonstrated is a flaw and may just be your own careless reading of the paper. What you’re illustrating is the kind of refereeing that gives refereeing a bad name.
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My central point is this:
Bell doesn't understand the data that went into his paper!!!
There are plenty of subtleties in AGN selection that could completely mess up his results. He discusses only a couple of the simplest, and completely ignores the rest. If he doesn't understand the creation of the catalog that he used to derive his results, why should I believe any of the results?
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Originally Posted by dgruss23
Has anybody compiled a radio galaxy sample from FIRST? The original 1997 is cited 316 times in ADS. I didn’t really see anything among that list that is a sample of radio galaxies fitting the purpose of Bell – but I may have missed something so feel free to check for yourself. The Stickel et al paper is cited 109 times as recently as 2007.
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Define "radio galaxy" for me, and I'll tell you. I do know that more than 20,000 FIRST sources have unique matches to SDSS galaxies that have spectroscopy (SDSS DR4 - there are more in DR6, but I haven't bothered to count yet).
I have no problems with the Stickel paper itself: it looks quite useful for certain purposes. But it was also a very biased sample of sources, by the nature of how it was created. If one wanted to compare two, supposedly different classes of objects, wouldn't one want to use uniform catalogs?
And, Bell says nothing about whether any of the Stickel sources are AGN of any kind (many, if not most, of them are). If the Stickel sources look just like some of his "AGN galaxies" spectroscopically, why should we believe that they should be treated differently from the VC-V sources? Bell does so because it is convenient for his "model."
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Originally Posted by dgruss23
Yes, sometimes papers need to be rejected, but not with the types of arguments you’ve made. Your strikes were either incorrect or ideas that could be presented to the author as avenue’s to explore for improvement.
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It was not my goal to referee the paper. But all of the things that I brought up should have come up in the review. And they make the results highly suspect, as I've noted above.
Do you believe otherwise?