Thanks for the interesting data.
I'm a little concerned about you said this in factor 4.
"4. HQケースを50個開けると、+1イヤリングを入手する確率は約90%、+2イヤリングを入手する確率は約9%となります。"
the literal translation is,
”4. if you open 50 HQ cases, you have about a 90% chance of getting a +1 earring and about a 9% chance of getting a +2 earring."
however, if 4. is "expected value of if we open 50 HQ cases"
we get about a 10% chance of getting only +1 earrings and about a 90% chance of getting at least one +2 earring, correct?
0.956^50=0.1054... and 1-0.1054=about 90%
as for the disparity per job, I was curious too, so I did some estimating and found that if the denominator is 1,024...
22*2 HQ earrings for 2 slots each job
44/1024 = 0.0429... about under 4.3% get some kind of HQ earring
2/1024 = 0.0195... Individually, about 0.2% each.
Assuming the remaining 980 slots are allocated to NQ earrings
54/1024 = 0.0527... About 5.3% are NQ earrings for standard jobs
41/1024 = 0.0400... About 4% are NQ earrings for extra jobs
44+54*6+41*16=1024
I'm just guessing, what do you think?
P.S. I’m not fluent in English, so I apologize if my expression is wrong.