Automated Topic Analysis of the Voynich Manuscript

[quimqu]

After building the topic models (LDA and NMF) described in my previous post, I projected the results over the full manuscript to see how the two main clusters  (which correspond closely to Currier A and B) are distributed across folios and handwriting styles. The analysis was done at two levels: folios and paragraphs.

At folio level, the two clusters are almost perfectly separated (about 92% agreement with the known A/B labels). At paragraph level, the separation remains strong (around 83%), but mixed pages appear more clearly (some folios contain both “languages” in different paragraphs).

Main results:

Currier	Pred A	Pred B
Language A	109	1
Language B	16	77

When folios are grouped by section:

Section	Dominant
Astronomical, Pharmaceutical, Zodiac	A
Biological (balneological), Marginal stars, Text-only	B
Herbal, Cosmological	Mixed

When compared with Currier’s hands, the correspondence is very close:

Currier hand	%A	%B
1, 4	~100	0
2	43	57
3, 5, X, Y	0–18	82–100

And when compared with the modern classification of hands (writting_hand), the same pattern emerges even more sharply. At paragraph level, small internal mixtures appear within some pages, but the overall pattern remains consistent:

writting_hand	%A (folios)	%B (folios)	%A (paragraphs)	%B (paragraphs)	Observation
1	1.00	0.00	0.984	0.016	Clearly A
2	0.00	1.00	0.078	0.922	Clearly B
3	0.097	0.903	0.081	0.919	Consistently B
4	0.933	0.067	0.805	0.195	Mostly A, with some B contamination
5	0.143	0.857	0.263	0.737	Clearly B but with more mixing than 2–3
@	0.00	1.00	0.231	0.769	Clearly B, with slight local variation