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DELTAprime
17th April 2017, 07:15 PM
Ok, I'm hoping that one of the teachers here (or maybe a D&D expert) might be able to explain this to me.

In Diablo 3 when you pick up a Legendary quality item you then have to click on the item to roll to get it's stats (essentially a virtual dice roll). There is a 89% chance it will be a standard Legendary, a 10% chance it will be an Ancient Legendary and a 1% chance it will be a Primal Ancient Legendary which is a item with perfect max stats.

Why is it that after clicking on hundreds of Legendary items over the weekend not a single one of them rolled as Primal Ancient? I thought that if it has 1% chance of rolling as a Primal that clicking on 100 would guarantee 1 of them would be a Primal item.

Ultra Mackness
17th April 2017, 07:31 PM
Interesting you've posted this - in Victoria we have a new study design for senior maths which includes this exact thing.

We actually have two things going on here that can't be mistaken for the same thing. First is the probabilities of success for the three outcomes you've mentioned. These exist as long term expected values or global aspects.

The second thing is the sample aspects. Each time you clicked out 100 of these virtual die rolls, you did a sample of 100, and there's absolutely no guarantee that in any sample of 100 that you'll get the sample aspects matching the global aspects, only a level of confidence that your sample aspects will match the global aspects.

In theory, you need to do about 33 of these samples (3300 clicks!) in order to be about 95% confident that your sample aspects will match your global aspects. Of course that also means that you're 5% confident that your sample aspects won't match. Downside is that this parameter can be tweaked by the game designers to crank up the number of samples you need to take, shifting 33 up to... well however high they want.

Either way, you'll still need to do a lot of clicking! Good luck!

Perceptor
17th April 2017, 09:43 PM
Have you unlocked GR70 yet?
if you havent primals dont drop
You must unlock GR70 to unlock Primals dropping

DELTAprime
17th April 2017, 10:03 PM
Have you unlocked GR70 yet?
if you havent primals dont drop
You must unlock GR70 to unlock Primals dropping

Yes I've completed GR70, just random chance is the issue.

Of well, a couple of hundred down, thousands to go by the sounds of it.

Facepunches
17th April 2017, 10:18 PM
Just powered a barb to 70 tonight and saw this. Ahhh seasons!

Paulbot
17th April 2017, 10:54 PM
Interesting you've posted this - in Victoria we have a new study design for senior maths which includes this exact thing.

We actually have two things going on here that can't be mistaken for the same thing. First is the probabilities of success for the three outcomes you've mentioned. These exist as long term expected values or global aspects.

The second thing is the sample aspects. Each time you clicked out 100 of these virtual die rolls, you did a sample of 100, and there's absolutely no guarantee that in any sample of 100 that you'll get the sample aspects matching the global aspects, only a level of confidence that your sample aspects will match the global aspects.

In theory, you need to do about 33 of these samples (3300 clicks!) in order to be about 95% confident that your sample aspects will match your global aspects. Of course that also means that you're 5% confident that your sample aspects won't match. Downside is that this parameter can be tweaked by the game designers to crank up the number of samples you need to take, shifting 33 up to... well however high they want.

Either way, you'll still need to do a lot of clicking! Good luck!

Maths is hard. :confused:

Ultra Mackness
18th April 2017, 04:55 AM
Maths is hard. :confused:

Hehe, I think of it as being a bit like whiskey - an acquired taste :)

Borgeman
18th April 2017, 07:20 AM
Yup. Since each roll is independent of each other, you start each roll fresh, previous rolls are irrelevant.
Probability is usually accurate as you tend toward infinity.

Your line of thinking is kind of like gamblers fallacy
https://en.wikipedia.org/wiki/Gambler%27s_fallacy

Ralph Wiggum
18th April 2017, 09:38 AM
Yup. Since each roll is independant of each other, you start each roll fresh, previous rolls are irrelevant.
Probability is usually accurate as you tend toward infinity.

Your line of thinking is kind if like gamblers fallacy
https://en.wikipedia.org/wiki/Gambler%27s_fallacy

i like this explanation.

tron07
21st April 2017, 03:52 PM
Computer random generator is not exactly random... hence you probably need to do it 2 times to get the accurate probability

like clicking 200-300 times, maybe you will get 2 of the the item you are looking for or if you are lucky can get 3-4 of them.