I thank Nikos Kokkinos for the thoughtful and informed engagement with the Qumran radiocarbon datings, and his comments are most welcome. I respond below point by point.
> Although I have not had the time to follow closely the > 14C saga of the DSS, working coincidently at present > on 14C questions in an area 1000 years earlier, I felt I > should look at what Doudna said on Orion. I know > Doudna's paper of 1998, and although I disagree with > his conclusion, I have liked his criticisms of the radiocarbon > method (informed it seems by Timothy Jull at Arizona). > In fact, I (and colleagues) have expressed similar criticisms > some years earlier (but also published in 1998 in Balmuth > & Tykot's 'Sardinian and Aegean Chronology', Oxford, > 29-43). Yet, I was surprised to read a somewhat defensive > Orion e-mail, when the problem really lies with the > radiocarbon method itself. I shall briefly explain. The defensiveness was not over radiocarbon issues, but over issues of misrepresentation with some history between Goranson and me on this point. > To begin with, it is futile to argue against "dismissal of outliers" > (Goranson) or against "data inerrancy" (Doudna). In any > focussed collection of 14C determinations the first rule of > interpretation should be "data inerrancy" (against Doudna) > and yet subsequent rules may inevitably involve the "dismissal > of outliers" (against Goranson), depending on individual > interpretations. This is the problem of 'probabilistic' statistics > applied to a scientific dating method, C14, which has a series > of inbuilt uncertainties - from the field to the lab and inter-lab > to the trees and stratosphere to stratigraphical interpretation. > The publications mentioned above give only a taste of such > uncertainties. Yes. > But in connection with the DSS the example given by > Doudna (4Q266) is not as good as it sounds. First, the > palaeographical date of this text is not as clearly cut as > presented ("pre-63 BC"). The script is semicursive and > quite careless, so a + date would be wise, most probably +. You are correct that the DJD palaeographic dating by Yardeni in the Baumgarten volume is 'should be dated to the first half or to the middle of the first century BCE', rather than "pre-63 BCE". But I referred to 'the pre-63 BCE palaeographic dating of 4Q266 (Da) *of Cross*" (emphasis added) in my Orion post. Cross indeed did determine that 4Q266 preceded 63 BCE on palaeographic grounds. I cited the reference at Doudna 1998: 460: Cross, _Ancient Library_, 1995 ed., 96, "[4Q266] can be no later than the first half of the first century BC...before the Roman conquest of 63 BC...by palaeographical evidence". (That is, Cross cited 'palaeographic evidence' as a positive argument for pre-63 BCE dating of 4Q266, which is meaningless unless he sees the palaeographic dating as requiring pre-63 BCE.) > Second, Doudna's calibration of the 14C determination > of the sample from this text (as with all of his calibrations) > is not to be accepted. Here Kokkinos is mistaken (though it is an honest mistake, and fruitful to explain). > Doudna used a version of CALIB > which he modified - not without reason but not an indefinite > one. He attempted to account for short-lived samples > based on a partial study reflecting single-year calibration > on wood from the US Pacific Northwest, post-AD1510. There is some misunderstanding here. There are two modifications at issue. CALIB is one of 3 or 4 standard computer calibration programs in common use. CALIB was produced at the U. of Washington at that time. Kokkinos uses OxCal, produced at Oxford, which is another standard one. Each of these programs use calibration datasets and are the interface to users being able to calculate and manipulate output based on the calibration datasets. The calibration datasets are the same in each of these programs, but the output is slightly different for each of the standard programs based on slight differences in how the math is done. These differences are tiny and in almost all cases insignificant, and again, these all derive from use of the same calibration dataset. However the calibration dataset itself has gone through corrections. The Zurich and Tucson datings were done using a standard 1986 dataset; later some problems were found with that dataset and for a few years an interim corrected 1995 dataset was widely used by the world's labs. In 1998 all of the labs and the standard calibration computer programs (CALIB, OxCal, etc.) switched to use a new 1998 dataset, which remains the one in use now in 2002. My calibrations were done on a CALIB program which was programmed for the 1995 dataset, which was reprogrammed with the 1998 dataset--that is, the *correct* dataset, the *same* dataset which Kokkinos's OxCal program (and all calibrations done today) use. The reason I had to modify a 1995-based CALIB was because the new 1998 dataset was not out yet and my article was due to Flint and VanderKam. I basically cajoled Paula Reimer at the U. of Washington lab--where the calibration dataset was being produced and updated--to give me the hot, new dataset before it was released or available to anyone. (In fact let me make this simple: she gave me a new disc with the 1998 program, but told me to call it a 'modification' of my old one, because officially no one was supposed to have this data before the release date. She was being helpful-- and it sort of had to be obscured by calling it 'modification' of my program for bureaucratic reasons.) When the 1998 CALIB became "officially" available, the underlying dataset had not been changed any from what was installed in my CALIB program (in the era at issue with the DSS). (I checked on that point.) Therefore the calibrations I have in Doudna 1998 are correct in terms of the most current basis used by all labs today in 2002. A second point is the detail of the modification for single-year uncertainty. The option of increased uncertainty factor is an option that all of the programs allow one to enter when getting calibrations. But here is the point, and it is important to grasp this: the *effect* on the calibrated datings--the output--compared to the calibrated datings that would have resulted if I had not entered that factor, was in no case greater than *2 calendar years*, and in most cases was 1 or 0 calendar years difference. (I ran the numbers both ways to check on this.) Since OxCal rounds up to the next 10 anyway, this second factor of the increased uncertainty based on the single-year data I entered can be elimininated as having any significance at all. > We now know that regional offsets vary considerably, and > we should have no idea what was the real 14C distribution > in Palestine of the first centuries. Until new and regional > calibrations become available the best thing to do is to > use the standard (and latest) OxCal98/2000 programme. The OxCal 98/2000 program uses the same dataset as CALIB 1998, which is what my calibrations in Doudna 1998 were from. The regional offset issue (discussed in Doudna 1998) is a separate issue and unrelated to anything to do with rejection of my calibrations using CALIB or preference for Kokkinos's using OxCal. (The regional offset issue is an additional uncertainty affecting both my and Kokkinos's numbers, and all reported radiocarbon calibrations in the world, equally.) I am not aware of any argument that OxCal is any better in principle in terms of its math/accuracy in running calibrations than CALIB, though having used both I can see why many users like OxCal for its user-friendliness. (Incidentally, anyone can download OxCal [also CALIB] for free from the Oxford lab web page; just enter 'radiocarbon lab' in any search engine and it is easy to find.) > This on my computer gives a date at two-sigma for 4Q266 > of 50 BC-AD 130. The upper end is not far from the > conventional palaeography at all. I published in Doudna 1998 for this: 44 BCE-129 CE. Again, this is from the identical dataset used by OxCal. The only difference is OxCal is programmed to round up (larger) to the next 10. 44 BCE gets rounded up to 50 BCE, and 129 to 130 CE. (I think OxCal's rounding to next 10 is sound reporting since single-year reporting is a misleading precision impression, though that is what CALIB does, as well as the original Zurich and Tucson DSS publications. It is a minor point.) > Doudna may say that he worked with one-sigma throughout. No, I agree with Kokkinos here on his emphasis that two-sigma (the 95% range) should be the key calibrated result of focus, and not one-sigma (the 68% range). For purposes of the 4Q266 example, I was thinking in terms of two-sigma. It goes as early as 44 BCE (or 50 BCE by OxCal's rounding up to nearest 10) compared to Cross's pre-63 BCE dating on palaeographic grounds. Cross's pre-63 BCE is outside of the two-sigma (though it is not outside of it by very much). > He should not have been advised to do so consistently > (though it is unfortunately the practice). The method has > yet to reach the point of dating confidently at one-sigma in > all areas and times involved (despite pretensions by > 'know-all-statisticians-cum-archaeologists who do not > understand what context, association and 'terminus post > quem' really mean). Here Kokkinos is right and I agree (though Kokkinos thinks he is arguing different from me). > The evidence is clear even within the > 14C saga of the DSS - namely the internally-dated Judaean > documents from the era of Bar Kokhba. For example, > XHev/Se 8a, the deed of sale at Kefar Barou (misspelled > by Doudna and others) dating to April/May AD 134 or (I used Milik's original mistaken reading Kefar Bebayou because that was the convention but I noted at Doudna 1998: 455 n. 67 that the correct reading is actually "Kefar Baru".) > February/ March AD 135 is calibrated at one-sigma as > AD 230-350 - only the two-sigma age range covers it > (AD 130-390). And there is no point for Doudna to > plead for 'contamination' here (which may or may not > be true) for this can be the case with almost all of the > DSS samples tested. The fact is that the two-sigma > age range indeed found the absolutely true date! Thus, > it is also a fact that radiocarbon dating cannot at present > determine a more precise chronology than +100 (or > perhaps even +150) years for any ancient document - > and particularly if this comes from a mini-14C disaster > area on the curve. > > Goranson will say (or rather in Doudna's interpretation > of Goranson) that therefore "data inerrancy" wins the > day. Goranson has stated that he does not wish to be identified with 'data inerrancy', and therefore my guess at Goranson's meaning was wrong. > But it does not do that, as I said at the beginning. > Look at the single, most strange example of the lot: > 4Q258 (Community Rule d). My OxCal cannot cope > with it even at the two-sigma age range: AD 120-320! > Actually not even the three-sigma (at 99.7% probability!) > is adequate: AD 80-330. The easy way out will again > be 'modern contamination' which I would strongly pray > it is the case (before I begin crying at Zeitlin's grave). > Another way will be to begin imagining copies of original > DSS deposited at the time of the Second Revolt (minus > palaeography) - as in followers of Bar Kokhba reading > old sectarian documents! But please do not raise your > fictional hopes - the 14C method has enough uncertainties > as already illustrated above. So at last here is an "outlier" > for Doudna. > > I need to go back now to the 14C results I am currently > checking of 1000 years earlier (there are other strange > battles there to be fought). I just thought to butt in - I > hope I said something useful. > > (This may be posted to Orion if anyone thinks it should.) > > Nikos Kokkinos Yes it was useful. Thank you. 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