D&D General 1 in 1000 chance

[Clint_L]

The oddities happen all the time.

There's about 8 billion people on the planet, and each of them lives a day with 1440 minutes in it. So, there's trillions of chances each day for something "weird" happening. Statistically, it is nigh certain that every minute of every day, several highly improbable things are happening.

We have this discussion in my theory of knowledge classes when we look at pseudosciences, coincidences, and miracles. Also, the sports ball players in the class react very skeptically when we study hot and cold "streaks" in sports and how they are mostly just a product of math.

 

[ilgatto]

Being an utter non-mathematician, I'm utterly stupefied to see folks here throwing about odds for certain die-rolls as if it's as easy as, well, pie.
So, if any of you could be so kind, riddle me this:

My 4th level Fighter (AD&D 2E) was fighting a bunch of orcs. The fight took 10 rounds, in which I managed to roll 5, 3, 1, 1, 2, 1, 4, 11 (missed), 6, and 4 - all of which made it an extremely bad day.

So what are the odds of rolling three "1"s on d20 in 10 rounds of combat?

 

[ad_hoc]

If you were going to post the result of this roll onto the forum regardless of what was rolled then it was a 1 in 1000.

The likelihood of eventually getting 3 10s during a gaming career is pretty high.

It's even more common place if we consider all exceptional outcomes on different sets of dice and from the rest of the players at the table.

It is interesting that the human mind naturally gets fooled by variance. It took playing a lot of poker and analyzing my hands to learn how common these sorts of things are expected to be.

 

[ad_hoc]

Being an utter non-mathematician, I'm utterly stupefied to see folks here throwing about odds for certain die-rolls as if it's as easy as, well, pie.
So, if any of you could be so kind, riddle me this:

My 4th level Fighter (AD&D 2E) was fighting a bunch of orcs. The fight took 10 rounds, in which I managed to roll 5, 3, 1, 1, 2, 1, 4, 11 (missed), 6, and 4 - all of which made it an extremely bad day.

So what are the odds of rolling three "1"s on d20 in 10 rounds of combat?

Very likely if we consider that we are looking at all instances of 10 rounds of combat in your playing career.

If we flip coins enough times we will eventually get heads 10 times in a row.

If we then ask how likely it was to get that result the answer is 100% because we were going to do it until we got that result.

 

[ilgatto]

Very likely if we consider that we are looking at all instances of 10 rounds of combat in your playing career.

If we flip coins enough times we will eventually get heads 10 times in a row.

If we then ask how likely it was to get that result the answer is 100% because we were going to do it until we got that result.

Well, yes, I can see the "philosophical" side of it. But that's not what I'm after, really. They were all the dice I rolled that night, so what are the odds if we count only that night?
I can see that there's always a 1 in 20 chance of rolling "1" on d20 any time you roll 1d20, but after that my brain just stops working.

 

[el-remmen]

Me: Look at this cool thing that happened!
Some People: Actually, it is not that cool.
Me: Uh. . . thanks?

 

[ad_hoc]

Well, yes, I can see the "philosophical" side of it. But that's not what I'm after, really. They were all the dice I rolled that night, so what are the odds if we count only that night?
I can see that there's always a 1 in 20 chance of rolling "1" on d20 any time you roll 1d20, but after that my brain just stops working.

We need to decide to only count that night before we roll the dice.

Otherwise it is like betting on roulette after it stops spinning.

My favourite magic trick is to have someone pick a card and then shuffle it back in. Let them shuffle it however they want. Make it completely random.

And then pull a card and say it is their card. It only works 1/52 times but the 1 time it works for someone it will be the most phenomenal trick they will ever see.

 

[Rabulias]

The oddities happen every once in a while.

The oddities happen all the time.

There's about 8 billion people on the planet, and each of them lives a day with 1440 minutes in it. So, there's trillions of chances each day for something "weird" happening. Statistically, it is nigh certain that every minute of every day, several highly improbable things are happening.

You're both right. Oddities happen all the time, and every once in a while they happen to me. It's the perceived rarity from a personal point of view that makes them stand out in memory when they happen.

 

[Benjamin Olson]

I once had a 5e PC roll double nat 20s at disadvantage in a contested roll against an NPC who also got a nat 20. I ended up ruling in favor of the PC, because it was more fun that way and felt more fair given that they had pulled off a 1 in 400 feat to the NPCs 1 in 20, but it was nice to have the added confidence that statistically I won't have to rethink the ruling until I've DMed another 8000 contested checks where one side has disadvantage.

 

[Stormonu]

Being an utter non-mathematician, I'm utterly stupefied to see folks here throwing about odds for certain die-rolls as if it's as easy as, well, pie.
So, if any of you could be so kind, riddle me this:

My 4th level Fighter (AD&D 2E) was fighting a bunch of orcs. The fight took 10 rounds, in which I managed to roll 5, 3, 1, 1, 2, 1, 4, 11 (missed), 6, and 4 - all of which made it an extremely bad day.

So what are the odds of rolling three "1"s on d20 in 10 rounds of combat?

For three rolls of 1 in a 10 round, that's what 3 in 10 x 20^3? So, about 1 in 2,400?