[Article] Topic Modeling in the Voynich Manuscript

[MarcoP]

BTW, also the fact that word structure is fairly consistent across sections while word frequencies vary so much is very puzzling.

Assuming that the ms was created with the use of external aids like tables, wheels, lists, external text, or something else, this could be explained by some portion of these aids or their content having been changed or replaced at points during the creation for various reasons. Has there been much discussion that different sections could have been enciphered differently? 

I think most people who are aware of the phenomenon think of it as an effect of different encodingsor writing systems. This idea however has problems of its own. See for instance what Rene wrote in his recent paper You are not allowed to view links. Register or Login to view.:

In the case of the original table-and-grille approach, a relatively easy explanation presents itself, namely that different tables were used for the pages in the two languages. However, this would not easily explain that almost all A-language words also tend to appear in the B language.

Another problem is deciding how many different systems (or "dialects") there are. The number of systems appears to be greater than the number of sections (e.g. the Herbal section appears to include two distinct parts A and B). Also Lisa's scribes do not seem to have a one-to-one correspondence to encoding systems or dialects, since scribe 1 wrote both Herbal-A and the different A variant in the Pharma aka Small-Plants section.

It is also possible that Voynichese is a single continuum with a slow "drift" in bigram frequencies. This would be even harder to explain. I think that Torsten is right in pointing out that also the plots in Sterneck et al. do not show well-separated clusters.