Chipped skulls dropping?

[Gdiil]

Ok i'm finding it odd that i've not run into a chipped skull. Did they stop dropping or has rate at which they dropped been decreased?

[Orphan]

Skulls always have a lower chance of dropping, when compared to the other gem types (2/20 chance, as opposed to 3/20 chance for each of the other gem types).

Other than that, there should be nothing preventing them from dropping.

[Thyiad]

Orphan, I bow yet *again* to your game mechanics knowledge. I had no idea that was in there. But it does make a lot of sense, now you have said it.

Now can you explain why my Baal runs *always* get Gloams which are convicted or might enchanted. Thanks in advance. :grin:

[Orphan]

Now can you explain why my Baal runs *always* get Gloams which are convicted or might enchanted. Thanks in advance. :grin:

Well, you have a 3/10 chance of getting Burning Souls in Baal's throne room. You have the same chance of getting Black Souls in Worldstone Keep level 2. As a result, you have a 3/10 chance of getting any souls in your baal runs, so pretty much every 3 games should net you some great soul packs.

Now, while the willowisps are not excluded from any particular boss modifier, I can only chalk the reason why you think you get those two modifiers more often is simply because you do not notice the times when you get the other modifiers :wink3:

Edit: My bad, did some wrong calcs.

[Thyiad]

Missed the edit time ...

Um, Orphy me old fruit ... it was a joke. It's a standing joke in any Baal run I host that you get nasty nasty boss packs of gloams. Usually with OKs or those :censored: dolls. Five dead MP'ers is my record; plus someone on a rescue mission. One of the dead was a level 96 sorc that solo's Baal at p8. Just never when I host.

You still know far too much :wink: :flowers:

[Orphan]

Um, Orphy me old fruit ... it was a joke. It's a standing joke in any Baal run I host that you get nasty nasty boss packs of gloams. Usually with OKs or those :censored: dolls. Five dead MP'ers is my record; plus someone on a rescue mission. One of the dead was a level 96 sorc that solo's Baal at p8. Just never when I host.

Heh I know, but I thought I'd attempt to answer it anyway :wink3:

[JME]

Well, you have a 3/10 chance of getting Burning Souls in Baal's throne room. You have the same chance of getting Black Souls in Worldstone Keep level 2. As a result, you have a 3/10 chance of getting any souls in your baal runs, so pretty much every 3 games should net you some great soul packs.

Now, while the willowisps are not excluded from any particular boss modifier, I can only chalk the reason why you think you get those two modifiers more often is simply because you do not notice the times when you get the other modifiers :wink3:

Edit: My bad, did some wrong calcs.

:scratch: I believe this would be additive. For the probability of, A or B, or A+B you would have a 3/5 chance in this case to have souls in your game....unless I'm serious forgetting some sort of rule. That would be a 60% chance to have them on any level and a 9% to have them on both.

I still bow to Orphan's D2 knowledge:brainiac:

EDIT: Krischan, you subtracted out the 9% of getting them on both, don't do that :) since you said "at least one" and not "only one"

[krischan]

You can have my OKs for your gloams. Deal ?

Regarding the 3/10 chance in WSK 2 and the throne room. Of course the chance to get them in at least one of the two is

1 - (1-3/10)*(1-3/10) = 51%.

[Orphan]

:scratch: I believe this would be additive. For the probability of, A or B, or A+B you would have a 3/5 chance in this case to have souls in your game....unless I'm serious forgetting some sort of rule. That would be a 60% chance to have them on any level and a 9% to have them on both.


I've said this in the past but I do not like probability :wink3:

Anyway, when I did the post last night I just thought that you have a 3/10 chance of getting black souls in WSK 2, and 3/10 chance of getting burning souls in throne, therefore out of the 20 possibilities of a monster spawn between those two areas, you have a 6/20 chance (or 3/10 chance) of getting any soul.

I only threw up the post as a response to Thyiad's question though, and I could be a little off with the probability. :tongue: If it is indeed a 3/5 chance of getting any soul creature, it goes to show why they appear so much. Krischan could also be correct in saying that there's a 51% chance. Still, it's very likely to get any souls.

[JME]

I've said this in the past but I do not like probability :wink3:

Anyway, when I did the post last night I just thought that you have a 3/10 chance of getting black souls in WSK 2, and 3/10 chance of getting burning souls in throne, therefore out of the 20 possibilities of a monster spawn between those two areas, you have a 6/20 chance (or 3/10 chance) of getting any soul.

I only threw up the post as a response to Thyiad's question though, and I could be a little off with the probability. :tongue: If it is indeed a 3/5 chance of getting any soul creature, it goes to show why they appear so much. Krischan could also be correct in saying that there's a 51% chance. Still, it's very likely to get any souls.

I know you were only answering just for fun, so was I.
Just to clarify, given your original probabilities:
There is a 30% to have souls in the WSK and a 30% for the throne room.
This means:
There is a 60% (3/5) chance to have souls in at least one level.
There is a 51% chance to have souls in only one level.
There is a 9% chance to have souls in both the WSK and the throneroom.

Statistics should be taught beside semantics. :wink:
This really explains why they are "always" there. The truth is, 3 out 5 times, they are.

Note: The amount of D2 knowledge you have compiled could probably snag you a job with blizzard. D3 by Orphan.:fortuneteller:

[LozHinge the Unhinged]

@JME - how do you get to 51% for Souls in one of the levels only?

I make it 42% - (30% x 70%) + (70% x 30%) ... but then, I truly suck at statistics. Thanks!

[JME]

@JME - how do you get to 51% for Souls in one of the levels only?

I make it 42% - (30% x 70%) + (70% x 30%) ... but then, I truly suck at statistics. Thanks!

P(A or B)= [P(A)+P(B)]-P(A&B) where the P of A & B is multiplicative

[LozHinge the Unhinged]

I was right all along - I suck at statistics! :grin:

[thegiantturtle]

given your original probabilities:
There is a 30% to have souls in the WSK and a 30% for the throne room.
This means:
There is a 60% (3/5) chance to have souls in at least one level.
There is a 51% chance to have souls in only one level.
There is a 9% chance to have souls in both the WSK and the throneroom.Sorry man, but these calculations are incorrect.

The first calculation is wrong. You can't simply sum 3/10 and 3/10 to get 3/5. These are independent choices. The chance to get at least 1 set of souls is chance for souls first time plus chance of no souls first time and souls second time. That's 3/10 + (1-(3/10))*3/10 = 51%.

The chance to get exactly one set is as LozHinge said: 3/10*7/10 + 7/10*3/10 = 42%

EDIT:
EDIT: Krischan, you subtracted out the 9% of getting them on both, don't do that :) since you said "at least one" and not "only one"krischan did not forget that. He was showing the compliment of not getting any souls at all, which is the easy way of showing at least 1.

P(A or B)= [P(A)+P(B)]-P(A&B) where the P of A & B is multiplicativeThis is incorrect. First or includes and. If you want it to be exclusive or, you need to specifically state that, say with xor. I already showed that the meaning behind the formula is wrong, so here are corrected formulae:

Exclusive or:
P(A xor B) = P(A) + (1-P(A))*P(B)
OR
P(A xor B) = P(B) + (1-P(B))*P(A)

Nonexclusive or:
P(A or B) = (1-(1-(P(A))*(1-P(B)))

[krischan]

I know you were only answering just for fun, so was I.
Just to clarify, given your original probabilities:
There is a 30% to have souls in the WSK and a 30% for the throne room.
This means:
There is a 60% (3/5) chance to have souls in at least one level.
There is a 51% chance to have souls in only one level.
There is a 9% chance to have souls in both the WSK and the throneroom.


No. :tongue:

The chance to have no souls in WSK2 is 7/10. It's the same with the Throne room. That means the chance not to have them in both is (7/10)*(7/10)=49%. The opposite to that is having them either in WSK 2 or in the TR or in both which is 100%-49%=51%, not 60%. The chance to have them in both is (3/10)*(3/10)=9%. Therefore the chance to have them in exactly one of the two is 51%-9%=42%, not 51%.

BTW, when a mathematician says "there is one...", he means "there is at least one...", else he says "there is exactly one..." :tongue:

[JME]

The first calculation is wrong. You can't simply sum 3/10 and 3/10 to get 3/5. These are independent choices. The chance to get at least 1 set of souls is chance for souls first time plus chance of no souls first time and souls second time. That's 3/10 + (1-(3/10))*3/10 = 51%.
The problem then is that you aren't including the calculation of getting them on both levels because they work independently of one another.

I ran a quick google search and pulled up this probabilities (http://www.regentsprep.org/Regents/math/andor/LProbAO.htm)
Somewhere in the middle is almost my exact formula
"Rule (for OR): P(A or B)= P(A)+P(B)-P(A and B)


and from hereanother site (http://www.mathgoodies.com/lessons/vol6/independent_events.html)
"Multiplication Rule 1: When two events, A and B, are independent, the probability of both occurring is:
P(A and B) = P(A) · P(B) "
This means the 9% for getting them on both is certainly correct.
...............
Apparently, I messed up the rules for (exclusive) independent variables involving addition, although the multiplication ones were sound. This is why, we both agreed on the 9% difference but disagreed on the starting point. Krischan's second post made that more clear (as well as the second half of TGT's. Please forgive me as I'm tired, at work, and constantly ready to go home. I think I'll join TGT in Act2 Spider Forest now :lipsrsealed: :embarassed: I suppose I goofed and stuck with it.

The general idea/statement, thankfully still reads true. A majority of the time, they are there. It's just 5.1/10 and not 6/10. Again, sorry I screwed up the first part. At least this is one time I can say I was closer than Orphan on something...Although, he was quicker to realize his fault and readily admitted it.:grin:

[thegiantturtle]

Apparently, I messed up the rules for (exclusive) independent variables involving addition, although the multiplication ones were sound.I think it's even simpler than that. As krischan said, you applied the formula for OR thinking it meant EXCLUSIVE OR. Don't beat yourself up about it. Using the wrong formula was probably the most common error I saw when tutoring and grading papers in college.

Furthermore, when I graded Introduction to Probability(Stat 451 (http://www.umbc.edu/UnderGrad/Catalog/pdfs/course_des_pdfs/STAT.pdf)) in college, probably a good third of the class made the exact same error as you. That class requires 3 years of Calculus and is really only for Math and Statistics Majors. At the time, it also doubled as Introduction to Probability for Statistics Graduate Students. What I'm trying to say is, even people that are planning to do this for a living mess that up shockingly frequently.

[JME]

I think it's even simpler than that. As krischan said, you applied the formula for OR thinking it meant EXCLUSIVE OR. Don't beat yourself up about it. Using the wrong formula was probably the most common error I saw when tutoring and grading papers in college.

Furthermore, when I graded Introduction to Probability(Stat 451 (http://www.umbc.edu/UnderGrad/Catalog/pdfs/course_des_pdfs/STAT.pdf)) in college, probably a good third of the class made the exact same error as you. That class requires 3 years of Calculus and is really only for Math and Statistics Majors. At the time, it also doubled as Introduction to Probability for Statistics Graduate Students. What I'm trying to say is, even people that are planning to do this for a living mess that up shockingly frequently.

Yes but I've taken through calculus 3, have a strong engineering background, nearly aced my statistics class, and work as a CPA. I shouldn't have screwed that up. Numbers are starting to get a little confuzzled:brainiac: Thanks for pointing that out and TGT esteem pre-buff.

[bhaberer]

you know whats really funny is the guy just asked about chipped skull odds and it turned into this haha :) you guys really know alot!