They are correct to the best of my knowledge based on the following assumptions:
- Each of the 3 random primary affixes are rolled in sequence (to prevent double element rolls etc.). Then given 3 of the 4 optimal affixes, movement speed is rerolled for the remaining affix.
- Amulets can roll primaries affixes according to this list of affixes found on items
- Each amulet affix has a different weight based on this data mined distribution
- The probability of primal ancient is assumed to 1 in 435 based on 10,000+ samples taken from botter data (the only good thing to come from botters).
- Primal ancient amulets have a guaranteed socket making the optimal affix combination more likely (but the chance of primal in the first place is low).
The probabilities were then calculated using Markov chains. Full details can be found in this post: So which do you think will be harder to get - #16 by Iria-1342