I tried comparing different ways of computing the lag-1 autocorrelation of word lengths in the Voynich:
- Global sequence (all words concatenated): +0.16
→ same result as Gaskell & Bowern, since long lines dominate and cross-line pairs are included.
- Line-by-line average (each line treated independently, then averaged equally): –0.07
→ negative, like what is usually seen in natural languages.
- Line-by-line weighted average (weighted by the number of word pairs per line): –0.03
→ almost neutral, but still slightly negative.
So the discrepancy comes from how the calculation is done:
- Looking at the whole corpus, the Voynich shows positive autocorrelation.
- Looking line-by-line, most sections, Currier hands, and scribal hands show negative autocorrelation.
- Weighting by line length pushes it closer to zero.
This suggests that cross-line word pairs and the dominance of longer lines are what make the global measure flip to positive, while within lines the tendency is closer to the short-term negative correlation typical of natural languages.
I have done the same calculations for different languages and a Torsten Timm generated text:
| Text | Global (within+cross) | Within-line | Cross-line | Weighted mean (per line) |
| Voynich (EVA) | +0.16 | –0.07 | +0.10 | –0.03 |
| Timm (generated) | +0.02 | +0.03 | +0.02 | –0.07 |
| Platonis Apologia (Latin) | –0.09 | –0.09 | –0.08 | –0.17 |
| Unfortunate Traveller (English) | –0.11 | –0.11 | –0.12 | –0.21 |
| Lazarillo de Tormes (Spanish) | –0.19 | –0.19 | –0.19 | –0.27 |
All three natural language texts (Latin, English, Spanish) show negative autocorrelation across the board, both globally and line by line.
Timm’s generated text shows near-zero / slightly positive global autocorrelation, but negative when measured per line.
The Voynich manuscript is the outlier: positive globally (+0.16), but negative line by line (–0.07 or –0.03 weighted).
The Voynich combines two opposing tendencies:
- At the global corpus level, it looks like Timm’s generated text (positive autocorrelation, even more unlikely than natural languages).
- At the line level, it behaves more like natural languages (negative autocorrelation).
- The difference between within-line and cross-line autocorrelation in the Voynich seems key. In natural languages, line breaks do not affect the measure, but in the Voynich they do: within-line is –0.07 while cross-line is +0.10, a gap of 0.17. This difference is unlikely to be accidental and suggests that line breaks play a structural role in how the text was generated.
This split behavior could be a clue that the line structure plays a central role in how the text was generated.