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If I understand dendrochronology, they are compiling--actual samples--a time schedule that will eventually be continuous all the way back, but that will vary from one region to another because climate varies from one region to another. Anatolia might have had a few good growing years while Attica was bone dry, for example, so samples could not in general be directly compared.

I wrote a paper on dendrochronolgy back in 1975 for one of my archeology courses. Very interesting topic. I don't share Mr. Keenan's lack of confidence in D-scores, though. I think it can become a useful statistical tool in this field.

If you had read the article, you would have known that D-scores were invented in the late 1980s (n.3). So you couldn't have known about, or even heard about, them in 1975. Also, contrary to your claim, the D-score does not exist in statistics. Keeenan (sect.2) states this explicitly. Even the researchers that Keenan is criticizing have acknowledged that (n.18).

If you are going to disagree with someone's argument, you ought to at least have looked at the reasons that they give for it. And you shouldn't pretend that you know what D-scores are.

Very interesting topic. I don't share Mr. Keenan's lack of confidence in D-scores, though. I think it can become a useful statistical tool in this field.

If the D-score doesn't exist in statistics, how can it become a useful statistical tool?

From the article:

D-scores

The D-score combines the g-score and t-score, via the following formula.

gt − t/2

The problem here is that the above formula has no apparent meaning. Consider, for instance, the obvious formula for the area of a rectangle: base × height. This formula is not just arbitrarily chosen; rather, it can be derived and shown to have the meaning “area of rectangle”. Similarly, the formula for the area of a square whose sides have length l is l², and again this formula is not arbitrary, but derived, and has meaning. The same is not true for D-scores. The choice of gt − t/2 is an arbitrary one among numerous formulae that could have been chosen to combine a t-score and g-score. For example, this formula might have been chosen instead.

gt²

There is no reason given for choosing one formula over the other. Furthermore, if the second formula had been chosen, then the wood from the gateway discussed in Section 4 would have been dated to 981 BC, rather than 1140 BC. This illustrates that the choice of the date for the wood (among dates with high g-scores and t-scores) is baseless—i.e. the date might almost just as well be chosen at random.