The Entity casing analysis

What are the rules behind the weird casing of the sentences from The Entity?
See the 'Interactive Translator' to turn your sentences into the special casing format
See the 'Word Variants' for all the casings probability used by The Entity in the game

Per-letter Uppercase probability

For each letter a–z, fraction of occurrences that were uppercase.

letters p_upper

Uppercase probability by Position in word

Probability that a letter at position k in a word is uppercase; far-right bin groups long words.

position heatmap