There has been a lot of confusion on the Web and in the media regarding the statistical probabilities cited in the Discovery Documentary as 600/1 that the Talpiot tomb is the tomb of Jesus of Nazareth. This conclusion, ultimately, but not directly, was based on the calculations of Prof. Andrey Feuerverger of the University of Toronto. I offer a few observations that I hope might clarify things in this regard.

As I see it, the basic calculations of the statistician, standing alone, do not in and of themselves establish whether or not the Talpiot tomb is, or is not, the likely tomb of Jesus of Nazareth. That determination, if it can be made, makes use of the math, but in the end takes one beyond simple probability calculations. What the statistician is asked to do is to determine the probability of the cluster of names, with their specific relationships and configurations, based on name frequency data in late 2nd Temple Jewish Jerusalem as well as other implicit factors.

Accordingly, a statistician, as statistician, is not primarily focusing on prosopography, that is, matching ancient names to known historical characters. That is the task of the historian who then seeks to determine if there is any potential “fit” between this cluster of names, with its configurations, and that of any identifiable persons/family in our records. Now if the “cluster” was sufficiently common, even if there might be some potential “fit” with some known individuals, then such a cluster would not be significant in terms of probable identification. So, for example, if we had a family group of x son of b, j, r, s, and t son of x, but we determined there would statistically be about 100 such configurations in a given culture/area/period, even if we came up with a “fit” in our historical records for this cluster, there would only be a 1/100 chance that the tomb we found was in fact that of the proposed family.

What happened with the Discovery documentary is that both these tasks, the statistics and Simcha’s proposed identifications (i.e., “fits”), were understandably linked into one. This could, however, give the impression that Feuerverger alone, on the basis of the “cluster rarity,” and its configurations was offering a 600/1 probability that Talpiot was the tomb of Jesus. There were also charges that Simcha had somehow set up Feuerverger by asking him to work with faulty assumptions. I have seen no evidence of any intent to deceive on the part of anyone involved. When several of us talked through this after the NY press conference, the Discovery executives were keen on clarifying whatever needed to be claified. Although the 600/1 probability was indeed the film’s conclusion, it could not be derived from Feuerverger’s stats alone, but only with the assumptions that Simcha was making in the film about prosopography. If the case of identification fails it is not because of “bad math,” but that the assumptions made regarding probable identifications do not hold up. Feuerverger has neither changed his calculations nor repudiated his initial work, as has been reported by some, although he has continued to work on a final version of his paper that is being written for his professional colleages. I think these issues have been clarified on the Discovery Web site and at Feuerverger’s Web site as well. [FN]

Feuerverger ended up focusing on just the four names in the specific form they occurred and the one relationship specified: Jesus son of Joseph, Maria, Mariamene, and Yose, as names potentially associated with the Jesus family based on textual evidence. His thinking was that if these four alone, as a cluster, could be shown to be sufficiently rare, then he could tell Simcha that although the generic forms of these names were indeed common, their specific forms, in these configurations, would not be. Feuerverger assigned frequency values to the individual names based on a synthesis of the figures in Tal Ilan and Hachlili. His initial calculation of 1/2,400,000 was quite high, but he then made two other moves that drastically reduced it. He divided by 4 for “unintentional biases in the historical sources,” and then he divided that result by 1000 to adjust for all possible 1st century tombs–thus his 1/600 computation.

Clearly Feuerverger is interested in the historical identification questions, as we all are, but he also recognizes this area is not his specialty. Math alone is not going to determine to what degree this cluster of names, in their configurations, are “appropriate,” or “highly appropriate,” as names for the Jesus family. That task, finally, rests upon the judgment of the historian who must make the case that such identifications are expected and likely.

It is of course quite possible to use statistics in ways that go beyond simple probabilities based on name frequencies and their specified configurations. I am not optimistic that more advanced statistical models can be effectively applied to questions of historical prosopography since the kinds of identifications and subtle correspondences used are not easily quantified. Is Mariamene an appropriate name for MM? How could you put a number on it? Is it significant that her ossuary is decorated and her inscription is in informal Greek? How is that quantified? Does it matter that the name Yeshua bar Yehosef is written in a very messy graffiti style while the others are elegant and block? How do you put a number on that? What of how the ossuaries were placed in the various kokim, and with names grouped in twos and threes? Are there hints of potential relationships implied? I have about 25 other factors of this sort that I am considering in formulating my own prosopographic proposal, including the symbol on the tomb that comes from contemporary temple gate imagery. As far as I can tell many of these factors can not be quantified.

I am not of course here implying that theoretical statistics are confined to simple probability theory. Obviously the application of advanced statistics has many applications of a complexity beyond the comprehension of the non-specialist. But in the case of the Talpiot tomb and its cluster of names, I think it has been demonstrated through simple probability statistics that although common as individual names, this “set,” with its specific configurations, would not occur hundreds of times in family tombs in and around 1st century Jerusalem. Whether the names are a good fit with those we know, or could expect, in a family tomb of Jesus is the matter at hand. The Discovery film has passed the ball now to the historians, the epigraphers, and the statisticians, and I anticipate the outcome will be enlightening to us all.

[FN]Dr. Andrey Feuerverger, professor of statistics at the University of Toronto, has concluded (subject to the stated historical assumptions) that it is unlikely that an equally “surprising” cluster of names would have arisen by chance under purely random sampling.

Taking into account the chances that these names would be clustered together in a family tomb, this statistical study concludes that the probability under random chance of observing a cluster of names as compelling as this one within the given population parameters is 600 to 1, meaning that this conclusion works 599 times out of 600.

A statistical study commissioned by the broadcasters (Discovery Channel/Vision Canada/C4 UK) concludes that the probability factor is in the order of 600 to 1 that an equally “surprising” cluster of names would arise purely by chance under given assumptions.

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