Comments on: Fair Dice

By: Four States of Interactivity @ Flechs

Four States of Interactivity @ Flechs — Tue, 27 Oct 2009 05:05:26 +0000

[...] I felt that touching on the “drama of the dice roll” seemed a nice foil to some nice scientific perspective elsewhere. (I’ve left out a semi-lengthy description of the game that might be redundant [...]

By: AWAD

AWAD — Fri, 16 Oct 2009 16:15:20 +0000

WOW!!!! This is what I needed about 2 years ago. Will send this on to an old player of mine that he was lucky but there was something odd about his dice. I checked them and they may have been had some manufacturing flaws as they were a little out of the norm., but nothing really out of the norm. (sorry after 100 throws I was done) Also he never understood while I got so pissed about his ability to throw odds, probability, and anything statistical out the door, not once but week in and week out.

By: Wantec

Wantec — Wed, 02 Sep 2009 14:52:40 +0000

The black and white dice with the rounded corners look like the ones that shipped with MechWarrior Dark Age and MechWarrior Age of Destruction starter sets.

By: quigs

quigs — Mon, 31 Aug 2009 20:16:30 +0000

All I gotta say is Brian’s next post better be some Omi Kurita porn to make up for this geekery.

By: EastwoodDC

EastwoodDC — Mon, 31 Aug 2009 12:23:58 +0000

Funny thing, I was just thinking about building my own dice tower that would allow full 3-axis rotation. It might also be a good idea if, after tumbling, the dice land on a padded surface to reduce bouncing and any tendency to fall onto the “heavy” side. A friend of my has a business doing laser cut acrylic, and I’m going to see if he can help me put something like this together.

By: Saxywolf

Saxywolf — Sun, 30 Aug 2009 02:19:14 +0000

@Paint-it-pink: Well, there are three kinds of lucky. Lucky because they are biased is what I’m concerned with. Lucky rabbits feet type dice and lucky because of how you roll them aren’t. however, I am keeping it in mind.

My problem with dice towers is that the common tower has ramps tilted around only 1 axis. The reason it is a problem is that with 6-sided dice (more so then other shapes), it will cause the die to tend to continue to roll around only that 1 axis. So, if you’re worried about a cheater, this will at least keep the chances of the number they want to 1 in 4, though without making it obvious I’d tend to think they were already at that level of chance. Towers are also kind of big so they take up precious table space. I saw a guy at GenCon using a cup. And that I liked. You just don’t see many people using either one.

Rolling and bouncing less enhances the probability of a cheater who holds them and rolls them in a certain way.

Rolling and bouncing a lot enhances the probability of a die to show it’s true probabilities. A biased die will show its bias while and a fair die will roll more evenly.

Thus casinos require you to throw the dice and use as fair dice as possible. Since we won’t be doing that any time soon for table top gaming, as good a compromise as one can find is what I’m really after.

By: Paint-it-pink

Paint-it-pink — Sat, 29 Aug 2009 19:04:06 +0000

Just as aside from all the statistics, caveat I don’t do statistics, I just have to be able to read and understand them in my day job, but I’m thinking that one of the best ways of reducing the effects of lucky dice, is to make all die rolls using a dice tower, as it will remove the bias that can be put on a die my how you roll it. Just saying is all.

By: Saxywolf

Saxywolf — Fri, 28 Aug 2009 03:29:52 +0000

@EastwoodDC: Besides your mention of possible un-uniform density, I really can’t think of a good explanation since GameScience boasts about how perfectly cubic their dice are.

haha… Not that I read the whole thing, but according to his standards, a perfect but dimpled die is unfair. You just need to roll it 10,000 times to see a difference of 25 rolls between the least occurring side (1) and most (6). So, according to the Energy State Model, my hypothesis was correct!

By: EastwoodDC

EastwoodDC — Fri, 28 Aug 2009 03:02:50 +0000

More: The Physics of Dice has results for a dice rolling machine performing tens-of-thousands of rolls. I found someone's Masters thesis on Fair Dice, which gives a fairly deep mathematical treatment of the topic. This will take me a while to read and understand, but I'll post about it when I do.

By: EastwoodDC

EastwoodDC — Fri, 28 Aug 2009 02:48:04 +0000

I too am disappointed with the Game Science die. I would expect better. You said it right, but I would add a clarification: where you say "Chi-Squared value" I would say "Chi-Squared p-value" or just p-value. This is the probability of the observed result (or one more extreme) if the die is actually fair. Small p-values are MORE likely to occur if the die is imbalanced. I wrote a longer post explaining the meaning of this Chi-square test.