What does “Die Fairly!” mean?
Are “Company X’s” dice fair?
Can you test my die?
How can you prove you rolled my die 1000 times?
How do you roll the dice?
Do you test D12, D10, D8, D6 or D4?
Do you roll every die 1000 times?
Why do you test dice?
After many years of this I realized no one had offered “tested” dice for sale. Of course, some companies purport to sell better manufactured, more precise dice that are “fair,” but those are hollow claims.
The only way to be sure is to roll the dice many times and do the math. So I built a robot to do the rolling, capture the numbers and do the statistics. I call her “Fortuna.” Named for the Roman goddess of luck and fate.
I test dice to keep the chaos in a tabletop game chaotic, not predictable.
What happens to the dice that fail your tests?
How do you evaluate the dice?
Why roll the dice 1000 times?
How do I interpret the graph for my die?
You will note that the graphs for all our dice have a “saw tooth” appearance. No die will exactly conform to the “perfect” outcome above. We use a “Goodness of Fit” statistical analysis to determine if a die rolls in an expected way as compared to a statistical benchmark. Please refer to the “Goodness of FIt” section of the FAQ for more information on this.
In case you are wondering, this is what a die that failed our testing looked like.
Rest assured, if we sell it on Lawfuldice.com, your die will never have a graph that looks like this!
What is “Goodness of Fit?”
Are Lawful Dice fair?
Some dice are so unbalanced that you can roll them only 100 times and see an unfair pattern. However, it may take thousands of rolls for another die to show its unfairness. As no die is perfect, roll any die enough times and it will become unfair eventually.
No one can promise a “fair” dice, but what we can do is guarantee that any die you purchase on our site rolled numbers in a distribution that fell within the expected outcome to a statistically significant number.
Promising any more than that is just not possible.
What does “P-Value” mean?
Fair warning, this part of the FAQ goes into the statistical weeds, so you are warned.
First, it should be made clear that a “p-value” is not a measure of die “fairness.”
“P-value” is defined by Wikipedia as follows:
In statistical hypothesis testing, the p-value or probability value is the best probability of obtaining test results at least as extreme as the results actually observed, assuming that the null hypothesis is correct.