Mapping Voynich connections through rare tokens

[Dunsel]

I think this opens a new way of checking for relationships between folios and sections.

You piqued my curiosity.  In the work I've done it's very apparent scribes had different methods and word shapes. Broadly, Currier A and B.  So I decided to see how your low count theory worked across scribes. I looked at hapax tokens that are unique to each scribe and then asked, how those tokens were shared with other scribes.  This would match your low count idea without throwing hapax out as noise. 

What I immediately noticed was the slow decline in similarity from scribe 1, which is Currier A, compared to the others.  Scribes 2-5 compared to each other looks mostly flat.

Hapax per scribe:

Scribe	Scribe-local hapax
1	1338
2	1261
3	525
4	298
5	210

Hapax matches to other scribe with Jaccard Overlap

Pair	Matches	Jaccard Overlap
1–2	105	4.21%
1–3	55	3.04%
1–4	37	2.31%
1–5	22	1.44%
2–3	80	4.69%
2–4	29	1.89%
2–5	31	2.15%
3–4	22	2.74%
3–5	29	4.11%
4–5	18	3.67%

Hapax matches to other scribes with Jaccard Overlap sorted by overlap

Rank	Pair	Jaccard Overlap
1	2–3	4.69%
2	1–2	4.21%
3	3–5	4.11%
4	4–5	3.67%
5	1–3	3.04%
6	3–4	2.74%
7	1–4	2.31%
8	2–5	2.15%
9	2–4	1.89%
10	1–5	1.44%

Some examples:

Token	Scribes
cheockhy	1, 2, 3, 4
odor	2, 3, 4, 5
ofaiin	1, 2, 3, 5
okody	1, 2, 4, 5

And here's another interesting tidbit. If I strip the gallows from those hapax tokens, that decline flattens out.

Hapax matches to other scribes with Jaccard Overlap with gallows removed

Pair	Matches	Jaccard Overlap
1–2	35	3.80%
1–3	21	3.05%
1–4	19	3.11%
1–5	16	2.74%
2–3	32	4.93%
2–4	22	3.79%
2–5	23	4.18%
3–4	8	2.31%
3–5	15	4.82%
4–5	10	4.22%

2-10 count word matches to other scribes with Jaccard Overlap

Rank	Pair	Shared Tokens	Jaccard Overlap
1	3–5	40	15.87%
2	2–3	81	12.27%
3	1–2	107	11.33%
4	4–5	15	10.07%
5	1–3	61	8.96%
6	3–4	22	7.80%
7	1–4	38	6.60%
8	2–4	32	5.51%
9	1–5	21	3.61%
10	2–5	18	3.09%

Checking all unique words instead of low count words didn't affect that table much.  But, through every test except hapax stripping, you can see the drop in similarity between scribe 1 and all the later scribes.

Rank	Pair	Shared Tokens	Jaccard Overlap
1	2–3	380	16.51%
2	3–5	145	16.00%
3	1–2	520	15.42%
4	1–3	292	11.95%
5	2–5	199	9.91%
6	4–5	61	9.84%
7	3–4	101	9.59%
8	1–4	192	8.83%
9	2–4	168	7.84%
10	1–5	139	6.54%