pair o' dice no paradox, men
The Urth list — 1 messages, 1 voices, 15 Dec 2001
https://urth.darkrealm.vip/thread/urth/2873

Exported from an unofficial mirror of a public mailing list. Copyright
in each message remains with the person who wrote it.

Email addresses are obscured as `user at host`, the form the original
archive published. This file was rebuilt from parsed fields rather than
retained headers, so it is faithful in content but not byte-exact.

==============================================================================

Michael Andre-Driussi — 15 Dec 2001, 15:43

Thanks Sunanda!

Joel Sieh also caught this and I thought he and I had posted to the list!
Here is my quote and response to him.

> > Joel Sieh wrote:
> > 6 different throws on each of two sided dice gives us 36 possible throws.
> > 
> > Possible combinations equalling 7:
> > 
> > Die 1	Die 2
> > 1	6
> > 2	5
> > 3	4
> > 4	3
> > 5	2
> > 6	1
> > 
> > Total combinations:  6
> > Probability = combinations equalling 7 / all possible combos
> > = 6 / 36 = 1 / 6 = 16.6%.
> > 
> > Following these calculations, rolls of 2 or a 12 would each have a
> > probability 1 / 36.  I agree that these are much less probable than
> > rolling a 7 (the most probable roll with two six sided dice), but it seems
> > that 1 / 6 is still against the odds, if you consider "against the odds"
> > to mean less than 50%.

> Wow, you are right!
> 
> What was I thinking?
> 
> Well, I was working off the fact that in games involving two dice, 7 is
> the middle of the bell curve.  I was erroneously thinking in terms of the
> odds of rolling >= 7 or <= 7 (which is a 58% probability), rather than
> just 7.
> 
> With regard to the text I was also puzzled as to why a 7 would mean death,
> when, for example, there are 10 men.  Up until the moment I typed it in, I
> sort of thought there were only 7 men, and the dice were saying how many
> would die (all, in this case); but the dice tell a group fate, not a
> fractional amount (all die or none die).  On my first reading I thought he
> was supposed to roll a number related to the number of crewmen, like, say
> = 8 (42% chance).
> 
> Even as I was typing it in this evening, and there was a glimpse of the
> truth (that rolling a 7 really is a 1/6 chance), I veered away from this
> and into the notion "Why not just use one die, if one-in-six is the
> desired probability -- then the roll of a =1= would make the whole thing
> quite obvious."  And the waste of a perfectly nice bellcurve (as opposed
> to the "flat" curve of a single die)!
> 
> (The reason why one-in-six is important is made clear in the text: that is
> the fatality rate for sunmen.)
> 
> The reason why a 7 means death is because that is the only way to squeeze
> out a 1 in 6 chance out of two dice!
> 
> Anyway, I was wrong.  Thanks for correcting me! (I still wonder why
> Harness would choose to use =two= dice when one die would work better.
> Well, work better for =me=, at least!)

Addendum: we both arrived independently at the notion that Harness is
probably talking about the dice game "craps," which, in the
pre-wargaming/pre-rpg world, was the most common exposure to dice games.

=mantis=


Sirius Fiction
Has Moved To
http://www.siriusfiction.com/

------------------------------------------------------------------------------