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sofawall
2009-08-21, 11:25 PM
What is the point buy equivalent of 5d6 drop 2?

What is the point buy equivalent of 5d6 drop 2, reroll all ones until you don't get a one.

What is the point buy equivalent of 5d6 drop 2, reroll all ones and twos until you don't get a one or a two.

What is the point buy equivalent of 5d6 drop 2, if you get 5 of the same number (yahtzee) you add them all together instead of dropping 2?

I'm pretty fail at statistics, and this seems above my limited abilities.

Luckily, however, I soon won't have these question, as I'm taking statistics in school this year :D

Kylarra
2009-08-21, 11:26 PM
Why would you want to have a potential 30 in starting stats...

Elfin
2009-08-21, 11:27 PM
Really, that seems a little to high.

sofawall
2009-08-21, 11:30 PM
I was curious, as I've seen every single one of these methods mentioned on the forums as being used by DMs, and I've always been curious as to their point buys.

BobVosh
2009-08-21, 11:48 PM
What is the point buy equivalent of 5d6 drop 2, reroll all ones and twos until you don't get a one or a two.

Isn't that just 5D4 drop 2, add 6? Seems more simplistic than rerolling constantly.

As for point buy:
What is the point buy equivalent of 5d6 drop 2? Unsure, not that good.

What is the point buy equivalent of 5d6 drop 2, reroll all ones until you don't get a one. You start at 8, so it should be the same as first choice

What is the point buy equivalent of 5d6 drop 2, reroll all ones and twos until you don't get a one or a two. Same as Above

What is the point buy equivalent of 5d6 drop 2, if you get 5 of the same number (yahtzee) you add them all together instead of dropping 2? It is a 1/46,656 that you get all 5 6's. Unlikely enough I would rate it above any other chances.Oh, any number? Slightly more likely at 7,776. But still not likely enough to change values for point buy. Go off the same number.

Milskidasith
2009-08-21, 11:55 PM
5d6b3 gets you a pretty good average; I generally find most of the time when doing it your dump stat is 9-11 and your good stats are 16-18, and you generally have one or two +3s.

If you roll dropping ones, you get a lot of extra dice added, so it's increased by a good bit; the worst roll you can get would be a 6, and that would be the same chance of getting a yahtzee. I would find it very rare to get under a 10 with it; generally 1s aren't ever even added into your rolls, so it's adding dice more than anything.

If you roll dropping 1s and 2s, it takes a yahtzee of 3s to have a true dump stat; you are more than likely to have your lowest stats be around 12 or 13.

With Yahtzee rules, it becomes impossible to have a true dump stat, but otherwise doesn't change much.

It's a good way to have a high powered game.

Random832
2009-08-22, 12:04 AM
I actually wrote a program that will make HTML bar graphs and calculate the mean and median for a function, so let's plug in a function to automatically roll this six times and calculate the point buy thereof...


What is the point buy equivalent of 5d6 drop 2?

Ends up being 38 points on average. (4d6k3, for reference, averages 28.5)


What is the point buy equivalent of 5d6 drop 2, reroll all ones until you don't get a one.

[rolled as 5d5k3+3]

Surprisingly (you'd think the ones wouldn't be statistically significant) it ends up being an average of 46


What is the point buy equivalent of 5d6 drop 2, reroll all ones and twos until you don't get a one or a two.

[rolled as 5d4k3+6]

I get an average point buy of 56.5 this way.


What is the point buy equivalent of 5d6 drop 2, if you get 5 of the same number (yahtzee) you add them all together instead of dropping 2?

That's just silly (and my dice statistics program isn't set up to handle it as easily). But 5 of the same number isn't particularly statistically likely (one in 1296 chance), so it's probably not significantly different.

Note that I calculated point buy for the above averages by assigning negative values to 7,6,5,4,3 rather than by dropping all results lower than eight (since a stat lower than eight is not possible for the point buy system). The average for 5d6 drop 2 went from 37.9 to 38.2 when i forced all results lower than eight to eight, and to 39.1 when i rerolled them. Rerolling 1s reduces the chance of getting less than eight, and rerolling 2s makes it impossible to get less than nine, so the differences will be less significant in those cases.

Now of course these are averages - you can get as low as zero (or even negative 30 if you allow stats less than eight and hit that one in two hundred sextillion chance of rolling ones on all thirty dice), or as high as 96, and I don't have a calculation for the standard deviation or anything more advanced.

sofawall
2009-08-22, 12:13 AM
Wow. That's a pretty huge difference for eliminating one result...

Thanks a ton!