Is testing your dice weight cheating?

[Jay R]

The purpose of a die is to generate a random number, in which every number has an equal chance of coming up.

If you use a die for which you know this is not true, then yes, you are trying to break the rules, and get an unfair advantage. It makes no difference if you found a die with an air pocket that rolls too many 18s and 20s, or if you chose to buy a weighted die or a die with two 20s and no 1s.

Trying to get more 20s than you have a right to is violating the spirit of the game.

If you are mistaken, and the die is fair, but you think it isn't, and so you roll it to get too many 20s, then you are still breaking the rules; you're just not doing it very well.

The game assumes a random number. Any attempt to get an unfair number of good rolls is ... well ... unfair.

[D+1]

So I tested my dice and found a few cheesex dice that were significantly weighed, the most prominent one seems so weighted it has a significantly higher chance of getting 2/18/20 but it still rolls pretty average out of 100 rolls. (Just rolled and got: 2,3,9,16,19,18,2,2,3,18)

Is it immoral to use this dice? What are your thoughts on checking your dice weights?

I firmly believe that short of using dice DESIGNED to cheat, any decently manufactured dice will roll randomly enough for ALL RPG purposes. Even if they ARE weighted by accident of manufacture to roll some numbers over others, I have yet to hear more than WILD, UNSUPPORTED tales of people that can roll dice with such skill as to get the number they want, or who can even detect a trend in normal play to prove any die is so biased as to be genuinely unfair.

Bias in dice is a sales pitch to get you to buy more dice (and probably pay more for them) and your DM and fellow players will NEVER detect a difference. For RPG purposes it's a lot of hooey. Take your set of sample rolls. Lots of very good, very bad, and nothing in the middle. Maybe it IS imbalanced that way. But will you know which you'll get? When you roll high will it be for a to-hit roll or a skill check? Can't predict that? Then the die is random enough IMO.

Also, if anyone feels that this is an edge they NEED/WANT in D&D they have far bigger issues than dice.

[kyoryu]

(Just rolled and got: 2,3,9,16,19,18,2,2,3,18)

That is highly skewed. Highly.

Your three 'weighted' numbers should come up 15% of the time, on average. In this case, of 10 rolls, HALF of them were in the 'weighted' range. Now, those were actually more 2s than 18s, but since the weight appears to favor both 18 and 20, if you find that the bias is towards them all relatively equally even (which it doesn't appear in this small sample set), then you'd have a significant advantage.

If you KNOW that your dice are imbalanced in your favor, and continue to use them, then yes, it is cheating.

Weighing your dice is not cheating inherently. But what you do with the information may be - if you weigh your dice and only use the least-imbalanced ones, then that would not be cheating at all. If you weigh your dice with the intent of finding the ones that are best biased towards you, then it would be.

[JoeJ]

That is highly skewed. Highly.

The chi square value for those numbers is 30, which is significant at the 0.1 level, but not at 0.05.

The results are highly questionable, however, because the sample size is so small. The rule of thumb is that you should have a number of rolls at least equal to 5 times the number of sides, or in this case at least 100 rolls.

[Jay R]

The chi square value for those numbers is 30, which is significant at the 0.1 level, but not at 0.05.

The results are highly questionable, however, because the sample size is so small. The rule of thumb is that you should have a number of rolls at least equal to 5 times the number of sides, or in this case at least 100 rolls.

I wouldn't use a chi-squared test with so few rolls, for the reason you just gave. The test has so little power with a small sample size.

[Willie the Duck]

Ten rolls, we should probably limit ourselves to non-parametric tests, along with limiting ourselves to drawing the kind of conclusions one makes with such analysis. Or we can ask the OP to roll it more.

[Jay R]

Having said that the test is low power with a small sample size, we can still do better by testing the specific question in front of us. [The more specific the test to the exact question you are interested in, the better the results.]

If we only test whether 2, 18, and 20 come up 15% of the time as expected, we get a χ² value of 9.61, with one degree of freedom.

That yields a p-value of 0.00194, so yes, even with this small sample size, we can reject the null hypothesis and conclude that those three values will continue to come up too often.

That conclusion is justified at an alpha level of 0.05, or 0.01, or even 0.002.

[Elysiume]

Is testing your dice weight cheating? Not necessarily.
Is testing your dice weight and then selecting dice that are biased towards high numbers cheating? Yes. You may not have purchased weighted dice, but you found out which dice of yours were weighted and chose to use them. If you know that something gives you an unfair advantage (with the caveat that in a cooperative game, "unfair advantage" is a term I've seen hotly debated) and choose to use it, you're cheating.

Would you sit down to play and tell the table "hey, I tested my dice and this one is disproportionately weighted towards high rolls so I'm going to use it"? If this feels like something you'd need to hide, you probably already know it's cheating.

[Ravens_cry]

Would you sit down to play and tell the table "hey, I tested my dice and this one is disproportionately weighted towards high rolls so I'm going to use it"? If this feels like something you'd need to hide, you probably already know it's cheating.

A fairly good rule of thumb in a relationship as well, on a side note.

[darkrose50]

So I tested my dice and found a few cheesex dice that were significantly weighed, the most prominent one seems so weighted it has a significantly higher chance of getting 2/18/20 but it still rolls pretty average out of 100 rolls. (Just rolled and got: 2,3,9,16,19,18,2,2,3,18)

Is it immoral to use this dice? What are your thoughts on checking your dice weights?

Just about all dice are weighted. They are tossed into a rock polisher and all the edges and corners are worn off to different degrees. Basically just about all of our dice suck, but some are more horrible than others.

Measuring something should just about never be considered negatively. We had one of those personality tests at work (though a third party that supposedly specializes in this sort of thing). Several of the questions were poorly written. One basically could be summarized as "do you look for loopholes" . . . with the assumption built in that anyone looking for loopholes is unethical. A company should STRONGLY want people that look for loopholes, and point them out. I wrote the company about a bunch of there questions, and was offered a job interview (I never took it, but it was flattering).

If the dice are swingy one way or the other, then you might want to replace them.

Someone has a service where they connect a Bobble-like-device to roll the dice, have a camera recording the results, and then a computer tallies the results.

[enderlord99]

This is a really messed up statement and I expected better on this forum. SHAME on you.

I mean, I'm a guy and I can confirm none of my appendages have memory (based on how awful my handwriting is) but I'm sure there are men with consistent, practiced penmanship and-

That's not what was meant by "male appendage" was it?

[kyoryu]

Measuring something should just about never be considered negatively.

Measuring is not negative.

What you do with that information can be.

[Rhedyn]

So I tested my dice and found a few cheesex dice that were significantly weighed, the most prominent one seems so weighted it has a significantly higher chance of getting 2/18/20 but it still rolls pretty average out of 100 rolls. (Just rolled and got: 2,3,9,16,19,18,2,2,3,18)

Is it immoral to use this dice? What are your thoughts on checking your dice weights?

If you are using empirical evidence to determine the best dice you have and then use those, then yeah you are cheating. You are effectively "weighing" your dice.

Now just using dice that you feel roll higher or using a bad empirical method, then no that isn't cheating.

[kyoryu]

If you are using empirical evidence to determine the best dice you have and then use those, then yeah you are cheating. You are effectively "weighing" your dice.

Now just using dice that you feel roll higher or using a bad empirical method, then no that isn't cheating.

100%.

Peoples' judgement of how random things are is usually pretty terrible, especially for short sequences.