There are three issues I ran into, for the Old Testament.
(1) There's many more books, plus I broke some apart (Isaiah 1 and 2, and JEPD). I probably should have broken Isaiah 3 out as well; maybe a future run. In any event, the larger number of books 'bleeds off' error, and results in smaller numbers to work with (where in the NT, a '25' would be high, here a '15' is high.
(2) As I previously discussed, the Old Testament appears to be three writing periods: Samuel-Kings-Stories, Isaiah-Deuteronomy-Prophets, and post-exile. Plus, what is so interesting is that books in each group have little to do with books in the other groups (in terms of syntax patterns).
(3) And, there's odd 'intrusive' patterns that suggest later editing. Jeremiah, Nehemiah and Ezekiel all can be found in small parts in the earlier books. You can easily see which books they worked on.
JEPD Document Theory I created 'pseudo-books' for each JEPD component, using one of the more accepted JEPD break-outs. Then I included them as potential 'authors'. Frankly, I didn't really get a good series of patterns from the break-out. Even though the break-outs appear logical, syntactically, the break-outs don't hold up at all. Definitely not 'Priest'. 'Deutero' is a little better. 'YHWH' and 'Elohim' are almost random, except for 'Elohim' stories in the last part of Genesis.
I did special analysis runs for the Torah, to try to strengthen the patterns (reduce the number of competing authors). I didn't see much change, but based on several analyses, I did conclude:
(1) Some sort of independent authorship is justified. 'Genesis', as a book, has a composite syntax much later than its components. And its components (in this case 'J' and 'E', but not 'P' or 'D') are much 'older' than the Samuel-Kings group.
(2) The 'J' and 'E' components influence later books throughout the series. (I ruled out both 'J' and 'E' as being late writers.) I'm guessing the 'J' and 'E' were common but separate sources until after the exile.
The spreadsheet below is a little different from what you saw for the New Testament. The gray blocks are the books, with those near the top 'earlier', and those further down 'later'. The green/yellow/red blocks are 'dating' positioners. Green indicates a consistency with other books, while yellow and red represent a conflict. In general, about a third of the positioners are conflicting. Within each positioner is the writer (eg JeJ) and a percentage distance. A high number (eg 15) means they're syntactically close while a lower number (eg 7) means they're syntactally distant. The groupings are trial and error to maximize the overall consistency. It's this 'grouping' that produces the dating sequence. Note: JeJ=YHWH Jee=ELOHIM JeP=PRIEST and JeD=DEUTO.
Illustration below:
[1] 1st and 2nd Samuel represent the key positioning books, with each of the other books reliably having a Samuel component for positioning. I have no idea when Samuel probably wrote. I'd assume from the internal stories, maybe 1050 bce or so, as a general dating anchor. Judges is earlier and is probably the earliest 'history'. I'd suspect it originally integrated many of the Ruth/Jonah/Esther stories.
[2] You'll notice Jonah, Ruth and Esther are 'early' books (higher). Initially I thought it might have to do with the 'story-telling' style. But more detailed analysis suggests that all three are probably quite early. If you're surprised by Esther, there are some later influences. I'm guessing that Esther didn't start out as a story from Persia. Of course the vocabulary mix is very similar to Ezra and company.
[3] Numbers is the 'first' of the identifiable Torah books. I suspect it was a composite of older histories put together at the same time as Joshua and the Kings group. You'll notice Deuteronomy is not in this group (some scholars thought Deuteronomy attached to Joshua/Judges and onwards as a history).
[4] You can not see the rest of the spreadsheet below, but there are no books that directly 'connect' to BOTH this Samuel group and the subsequent 'Isaiah' group. Mathematically 2 Chronicles connects to both the Kings and Isaiah, but that is because of its direct copying of Kings.
Interpeting this, some of the relationships are quite strong, so I'd assume there is some truth to the 'layout'. Being the 'guesser' that I am, I think Samuel was a very strong influence on early Israel, with his documenting 'tradition' carrying into the time of the early kings. Given the complete break between this group and the next, I'd assume that when the Solomonic kingdom broke up, there was a sea-change in the writings and writer-groups. I haven't done enough analysis to see whether it's a north/south pattern as some have suggested. But something definitely changed dramatically.
Go to next page for the Isaiah group of books.