# a quick primer on probability when rolling dice

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do you guys work at the DMV or something where administratium is at toxic levels? my link explained what event he was referring to, and why it was termed as common core, because that's how the story was widely circulated.

I'm simply repeating myself at this point, but the link you cited as evidence that Common Core is bad actually says, in large bold letters:

This is NOT a Common Core standard.

So either you didn't read it, or you read it but didn't understand that it dramatically undercuts your point, or you read it but assumed no one else would read it.

At this point, I honestly have no idea what's going on here. You posted a misleading-at-best topic post on statistics and probability, got called on it, refused to admit you'd been caught in an error, attempted to deflect criticism by making it a conversation about education policy, made another error, and now you're attempting to deflect criticism by... accusing people of working at the DMV? Welcome to my block list.

I guess the old notion that (a*b) = (b*a) or that (A + B) = (B + A) must not be getting taught anymore.  Either that or maybe it's just not right anymore although it has always worked for me.

Just to be clear, commutativity definitely is being taught. Someone teaching third grade didn't know it, which happened to tie into a popular narrative against a particular education-policy initiative, and which went viral with the help of Reddit--but it has nothing to do with how math is typically taught, or for that matter with any policy or curriculum.

Back on the topic of probability a lot of people seem to have trouble with things especially as you start going beyond the simples...

People--by which I mean human brains--are notoriously bad at handling probability. We have a lot of cognitive biases and what seem to be built-in misconceptions, probably because when our brains were subject to strong selection pressures, detecting patterns even at the risk of false positives had immediate life-or-death value. It's why we have careful mathematical tools for dealing with this stuff, but that has the downside that those tools require training to use well.

But I also think it's a bit unfair to ascribe every "it's not fair!" complaint to ignorance or bias. One of my favorite examples is getting Soontir Fel one-shot by an Academy Pilot at Range 3, through an asteroid, with Autothrusters and Stealth Device. When I put Fel there, I was making an implicit bet that the dice results wouldn't be so far from the median result that he'd die. And that's a really safe bet!

To kill Fel, my opponent had to roll two successes that included a crit (10.9%), I had to blank my defense dice (0.3%), then he had to draw a Major Explosion (6.1%), then roll a hit (37.5%), then draw a Direct Hit (21.9%). The odds of actually doing all that are 1 to more than 650,000 against.

That's an extreme example, but when all you need to keep your Phantom alive is 1 lousy evade on 4 dice, or all you need to wipe out a Lambda you've been chasing for three rounds is to get at least 2 hits with a focus token and you keep failing, blaming "bad luck" can just be a less-explicit way to say "if I'd seen the median result for this game state, the situation would be much more in my favor!"

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:CCSS.MATH.CONTENT.3.OA.A.1 (3rd Grade)Interpret products of whole numbers, e.g., interpret 5 × 7 as the total number of objects in 5 groups of 7 objects each. For example, describe a context in which a total number of objects can be expressed as 5 × 7.

That does vaguely bother me since it can also be 7 groups of 5 objects each, but I am a programmer with 0 training in education so I'll just assume the experts aren't stupid.

*sigh*

This is one of MANY standards. I picked one at random. It's not saying it can't be visualized as 7 groups of 5, or 5 of 7, just as a 3rd grades (average age, what 8 years old) should be able to think of it as groups of objects. It helps the numbers become real vs just a foreign language on a page. It's also not specifying the way to teach this standard, just what kids should understand at what age to create a baseline.

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But of course we all know that in reality we should use conditional probability theory rather than probability theory when calculating all those numbers between 1 and 0.

Bayesian updating might be appropriate.

Sorry if this is off the mark, I only managed a Masters from the fourth oldest University in the English speaking world.

Cheers

Baaa

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But of course we all know that in reality we should use conditional probability theory rather than probability theory when calculating all those numbers between 1 and 0.

Bayesian updating might be appropriate.

Sorry if this is off the mark, I only managed a Masters from the fourth oldest University in the English speaking world.

Cheers

Baaa

Psh. Is that all? You're just an... uh... you're so dumb, you...

Er, this is a bit embarrassing. I don't know enough negative stereotypes about Scots to say something ironic and cutting here. Would you do me a favor and fill in the blank?

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Pretend like you can't be bothered to learn the difference between a Scotsman and an Irishman, and then insult the Irish.

Now you've got lots of people mad! Efficient!

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But of course we all know that in reality we should use conditional probability theory rather than probability theory when calculating all those numbers between 1 and 0.Bayesian updating might be appropriate.Sorry if this is off the mark, I only managed a Masters from the fourth oldest University in the English speaking world.CheersBaaa

Psh. Is that all? You're just an... uh... you're so dumb, you...Er, this is a bit embarrassing. I don't know enough negative stereotypes about Scots to say something ironic and cutting here. Would you do me a favor and fill in the blank?
Erhm, can't think of anything off the top of my head. Except I really don't wear underwear when I have my kilt on for haggis hunting.

Cheers

Baaa

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But of course we all know that in reality we should use conditional probability theory rather than probability theory when calculating all those numbers between 1 and 0.Bayesian updating might be appropriate.Sorry if this is off the mark, I only managed a Masters from the fourth oldest University in the English speaking world.CheersBaaa

Psh. Is that all? You're just an... uh... you're so dumb, you...Er, this is a bit embarrassing. I don't know enough negative stereotypes about Scots to say something ironic and cutting here. Would you do me a favor and fill in the blank?
Erhm, can't think of anything off the top of my head. Except I really don't wear underwear when I have my kilt on for haggis hunting.

Cheers

Baaa

Ha! You can't fool me that easily. Haggises (haggi? haggides?) don't run around to be hunted! They're some kind of very strange vegetable, I think.

Bugger. Caught.

Cheers

Baaa

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That's a Burns Supper.

Cheers

Baaa

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[...]

"bad luck" can just be a less-explicit way to say "if I'd seen the median result for this game state, the situation would be much more in my favor!"

I want to say this at some future game but I have to gauge the crowd first.  But in the right circumstance, it could be hysterical.

Hmm, I wonder if I can work this into a signature such as:

If it wasn't for the median result for this game state which isn't in my favor,

I'd have no random occurrences  to (insert something really cool here) at all.

Or something like that but more witty, something I apparently am not.

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the chance of rolling a hit or crit on a red dice is 50%, or 0.5 in math notation

::kisses fingertips::

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But of course we all know that in reality we should use conditional probability theory rather than probability theory when calculating all those numbers between 1 and 0.

Bayesian updating might be appropriate.

Sorry if this is off the mark, I only managed a Masters from the fourth oldest University in the English speaking world.

Cheers

Baaa

Slacker, huh? <vbg>

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Trying to simplify things frequently leads to incorrect conclusions.  This thread is a perfect example.

If people would stop trying to baby others, perhaps more people would actually understand it and not throw up their arms and say "Math is hard".  I'd like to think that any person is capable of understanding it given time and a slight bit of effort if you don't try to dumb it down.

OP, I appreciate the idea and effort, but I expect there are more people confused by your post/this thread than were helped by it.

He wasn't trying to simplify anything. Plainly, he just doesn't know what he's talking about.

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But of course we all know that in reality we should use conditional probability theory rather than probability theory when calculating all those numbers between 1 and 0.Bayesian updating might be appropriate.Sorry if this is off the mark, I only managed a Masters from the fourth oldest University in the English speaking world.CheersBaaa

Psh. Is that all? You're just an... uh... you're so dumb, you...Er, this is a bit embarrassing. I don't know enough negative stereotypes about Scots to say something ironic and cutting here. Would you do me a favor and fill in the blank?
Erhm, can't think of anything off the top of my head. Except I really don't wear underwear when I have my kilt on for haggis hunting.CheersBaaa
Ha! You can't fool me that easily. Haggises (haggi? haggides?) don't run around to be hunted! They're some kind of very strange vegetable, I think.

Think of haggis as the original 'boil in the bag' meal.

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Think of haggis as the original 'boil in the bag' meal.

Gigantor dumplings!

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I almost stopped reading the OP when I got to that 6% times 10 makes 60% probability, but I thought I better carry on and read through the answers. Admittedly I haven't read all of them, especially the ones on the last pages, that seem to be rather off the original topic.

At some point during the reading process I got to this answer:

the criticizers above were themselves incorrect in their terminology, instead of (correctly) saying that my terminology was wrong, they instead (incorrectly) said my math was wrong. my math was not wrong, it was only (incorrect) colloquial terms and excessively rounded digit, both choices being done on purpose.

Far from being the only answer that almost makes me cry, but perhaps the most relevant. I thought this deserved a solid, almost rude and improper reply. It probably still does. But then I thought I would try to reply as constructively as I could:

What you say in the OP is wrong. Fact. It is hard to decide whether it is the terminology or the maths because Maths should be spoken in the language of Maths, which is a very formal one that doesn't allow any "room for interpretation". You seem to be saying that you knew your terminology was wrong, yet decided to carry on with it anyway. I think it is to be expected that people will tell you that your maths were wrong if you don't explain them using the right words.

- Johnny has 4 bananas and 6 apples. Johnny gives 2 bananas and 5 apples to Rose. How many apples does Johnny have?

- 2, Johnny has 2 apples!

- Wrong! Johnny has 2 bananas and 1 apple!

- Oh, no no no no no, when I said apples I meant bananas! Don't be so unflexible as to not understand that "apples" means "bananas"! We all knew what I was talking about!

I think you did something similar with your explanations.

I appreciate you were trying to help with your OP, that's a good thing, but I think it's extremely unproductive to try to teach people using concepts and words that you know are wrong, as it does not help in understanding. Going around writing things that are wrong and saying "oh, I wasn't trying to be technical" doesn't make anyone a favour. You will be criticised, and people trying to learn from your posts will learn the wrong thing. Loose/loose situation if you ask me.

My constructive suggestion would be that you edit the OP and change that "60% chance" into a 0.6 average, or 60% average (although that's a strange term), or whatever you want to call it. Anything except "chance", because that's not what it is.

If you know it's incorrect, why not fix it?

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I'm terrible at probability and it's cousins, as I can't keep them straight. Never kept it straight in school. Could anyone direct me somewheres to learn them again?

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I'm terrible at probability and it's cousins, as I can't keep them straight. Never kept it straight in school. Could anyone direct me somewheres to learn them again?

There are a couple of good ones on Binomial Distribution.  Wolfram has one: http://mathworld.wolfram.com/BinomialDistribution.html

And here is a PDF from Notre Dame: https://www3.nd.edu/~rwilliam/stats1/x13.pdf

For starters

Edited by Ken at Sunrise

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I'm terrible at probability and it's cousins, as I can't keep them straight. Never kept it straight in school. Could anyone direct me somewheres to learn them again?

There are a couple of good ones on Binomial Distribution.  Wolfram has one: http://mathworld.wolfram.com/BinomialDistribution.html

I was most disturbed by another link on this website which said "Recreational Mathematics".

Psst, I've got some £10 bags of illegal equations, guaranteed to blow your mind.

Cheers

Baaa

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I'm terrible at probability and it's cousins, as I can't keep them straight. Never kept it straight in school. Could anyone direct me somewheres to learn them again?

There are a couple of good ones on Binomial Distribution.  Wolfram has one: http://mathworld.wolfram.com/BinomialDistribution.html

I was most disturbed by another link on this website which said "Recreational Mathematics".

Psst, I've got some £10 bags of illegal equations, guaranteed to blow your mind.

Cheers

Baaa

LOL but come on some of there are fun.

I remember, I won't say how may years ago, we were in geometry, sides angles and such.  We were reviewing these theorem.  So I asked the instructor why we didn't cover Side-Angle-Side and she said because it would be in appropriate.  Huh?  Really?  Now after all these hears it is on the "Recreational Mathematics" page under "Humor" and called the ASS Theorem: http://mathworld.wolfram.com/ASSTheorem.html

Go figure.

But this is my all time favorite:

If you don't know and don't want to figure it out scroll down because I don't know how to do spoiler tags:

Be greater than average

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I quickly read the paper from Notre Dame and have a question as it relates to X-Wing. Are we only interested with the possible combinations of dice results or the permutations? My gut reaction is combinations. We don't care what order the evades or hits come up only that they do. Am I right? If not I need two more cups of coffee and more paper.

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I quickly read the paper from Notre Dame and have a question as it relates to X-Wing. Are we only interested with the possible combinations of dice results or the permutations? My gut reaction is combinations. We don't care what order the evades or hits come up only that they do. Am I right? If not I need two more cups of coffee and more paper.

Right, we're only interested in combinations. Hit/crit/hit has the same value, for us, as hit/hit/crit.

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I'm terrible at probability and it's cousins, as I can't keep them straight. Never kept it straight in school. Could anyone direct me somewheres to learn them again?

There are a couple of good ones on Binomial Distribution.  Wolfram has one: http://mathworld.wolfram.com/BinomialDistribution.html

I was most disturbed by another link on this website which said "Recreational Mathematics".

Psst, I've got some £10 bags of illegal equations, guaranteed to blow your mind.

Cheers

Baaa

Three of them are already spoken for, right?

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I quickly read the paper from Notre Dame and have a question as it relates to X-Wing. Are we only interested with the possible combinations of dice results or the permutations? My gut reaction is combinations. We don't care what order the evades or hits come up only that they do. Am I right? If not I need two more cups of coffee and more paper.

Right, we're only interested in combinations. Hit/crit/hit has the same value, for us, as hit/hit/crit.

Aha! I'm not a complete MCF!(Math Challenged Fool)

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