3D dice results are not random

[Weissrolf]

For comparison: PCG32 is the least complex form of the PCG family of random number generators and can be implemented with only 10 lines of code. Creating 10 gb of random data takes 26 seconds, corresponding to over 10 billion D256(-1) rolls. It succeeds with a test sequence length of 8 gigabytes where FGU's D8 already fails with a length of 8 kilobytes.

length= 8 gigabytes (2^33 bytes), time= 379 seconds
  no anomalies in 1545 test result(s)

FGU's /die 256-1 fails at 64 kilobytes in comparison (and builds up suspicion before that).

[Weissrolf]

Indeed. You compiled all this data comparing apples to oranges and then came here to conclude that not only are apples not oranges, there is something wrong with our apple because is it not an orange and we should get rid of it ...

I compiled 375000 bytes of random data created via FGU D8 rolls and compared that to 375000 bytes of random data created by other RNGs (including FGU's /die). What exactly is it you like to contribute to the discussion by your snarky remark?

But let's just forget about the comparison: I sent FGU's rolls through well established randomness test applications and its D8 rolls fail easily and early. Why would you not want to get rid of such a very bad RNG?

And no, with a period of ebbs and flows within just 200 D8 rolls it is not even good enough for our usage scenario.

[Kelrugem]

It's rather impossible to do. We are not scientists here who even understand what this all means beyond fail and success. There just is no way to give a "short introduction". These are well established randomness tests and all we can do is trust their results, just like scientists around the world trust them and test them. Everyone wanting to go deeper needs to read through manuals and web-sites of scientists/coders who create and test random number generators (and even their disputes in papers and forums), and possibly study mathematics.

The first bitmap image is the most down-to-earth representation of FGU's PRNG failure I can give you. It is pure visualization of the numbers FGU rolled as black/white dots and should display random noise. Instead it displays visibly repeated patterns. That must not happen!

I did far more work on this than I should have done, but this represents a real number-crunching examination of FGU's physical dice results, free from any "I rolled too many crits today" bias. Not psychology, but mathematics. Does it go over my own head? Sure, but that's why Practrand tries to categorize it in readable fails and suspicions for dummies like us.

No worries, I do not expect that you give proofs of all that stuff and how it works Let me clarify, I am a scientist (my field is sadly not statistics etc. sadly, would it have been about curved Yang-Mills-Higgs gauge theories or something like that then I could be more specific ), and it is not just important to derive results but also to convince others of your results; especially the latter can be more difficult than deriving a result Of course there is trust needed when scientists and non-scientists speak with each other But when presenting results, one needs to think about who is the target audience and, based on that, you adjust how you present the result When I want to explain non-experts, what the Higgs boson is, I will not present the Yang-Mills-Higgs Lagrangian for example Do you know what I mean?

So, what I asked is just basically: What did you do actually? Your answer to LordEntrails gave some information I would have liked to see in the first post: So, sample size of the d8 rolls (an estimation of), and then what you did with them. Something like "I used these results to insert them into this programme which measures randomness", so, just some explanation of what you actually did; you do not need to explain what all of this means, but you directly started with the results and I had no idea what you actually were doing and were all of this came from I felt immediately lost. I needed to read your answer to LordEntrails to actually understand what you were doing and what the first graphic was about All the informations which non-experts cannot understand I would have simply omitted, just saying "when using that randomness-checker, I got a Fail as result", maybe uploading your d8 results (probably you have saved them?), such that someone else could check, too, if needed Especially SmiteWorks themselves for example

So, after reading your answers I now know what I would have liked to know in the first post already (to avoid that people get lost directly)

But of course I do not demand anything of that, just a comment about how it reads EDIT: In some essence, you could just copy parts of your answers here into the first post for readability

[LordEntrails]

If it says "Fail" in too many tests then it's not random.

I get that part

Sorry, but I really don't understand the question?! What range do you mean?

What I meant was something like this, out of 200 d8 rolls, my non-scientific, engineer only, brain would expect results like this;
Roll of 1 had 25 occurrences.
2 had 23
3 had 26
4 had 26
5 had 27
6 had 24
7 had 25
8 had 24

Something like that would be one thing (and maybe close to random?) but something like this;
1 had 5 occurrences
2 had 50
3 had 7
4 had 35
5 had 11
...

Would be very far from expected random results.

What I did was to create binary data out of the dice rolls where each byte consist of numbers 0-255. Since FGU's physical dice cannot roll D256(-1) I rolled D8(-1) instead, stripped the five 00000 high bits and formed one long bitstream of 375000 bytes (=1 mio rolls of D8). Each D8's binary representation is between 000 to 111, 2.67 D8 make one byte between 00000000 to 11111111. For comparison I did the very same with random.org rolls of 0-7.

Is that a methodology from one of the sites or is it something you came up with? I have no idea, and have no idea how to figure out, is it a valid methodology?

I do know other folks have claimed to have run analysis of chatlog.html rolls (actual campaign data) and have always come back and said that the results was within expected distributions. Now I have no idea their methodology(ies) or such. But it might be worth seeing if someone can find those old posts and analyses.

The first image is a bitmap where each binary 0 is black and each binary 1 is white. I found out that there is a period of only 600 pixels/bits where you see the ebb and flow of dark and light areas repeat in the bitmap image. 600 bits = 75 bytes x 2.67 = 200 rolls of D8. The image does not tell us which results were rolled, but it tells us that there are periodic ups and downs of more 1 bits vs. more 0 bits in the stream of consecutive rolls.

Again, not everyone has to understand what this all means, all you need to see is that both PCG and random.org look like random noise (the kind of static noise you may remember from old TVs), but FGU's D8 rolls show a clear periodic pattern.

The graphics are interesting, and with this explanation it makes sense now. Thanks.

[smelton]

It's not a snarky remark .. more like a perfect analogy to summarize this thread. You are comparing a physics simulation (apple) to RNGs (oranges). No RNG is used for the 3D dice. If you want RNG, use /random or write an extension using your preferred RNG algorithm.

[Weissrolf]

So, what I asked is just basically: What did you do actually?

Ah, of course, this I can do. I left all the explanation out, because if no one at SW was interested in the result and people come „pfff“ and „Blabla“ at me again then by do even more work?!

I am in bed now, but can write that down for you tomorrow after finally playing chess with my daughter (she kept asking).

I felt immediately lost.

I thought the visual comparison of FGU creating patterns where others create (TV like) noise was strong and clear that it already proved the main point. I was wrong in that.

maybe uploading your d8 results (probably you have saved them?),

I did, but how much more can one do with 1 mio. D8 rolls than what I did and no one here seems to have done before? I decided to offer these only per request, especially after being somewhat ridiculed for doing so many rolls. I also omitted results like average and such, because they were unsuspicious.

There are more randomness tests out there that are harder to use (even more so on Windows) and don‘t seem to produce better result.

Diehard
Dieharder
NIST
TestU01

[Weissrolf]

It's not a snarky remark .. more like a perfect analogy to summarize this thread. You are comparing a physics simulation (apple) to RNGs (oranges). No RNG is used for the 3D dice. If you want RNG, use /die or write an extension using your preferred RNG algorithm.

So the physics engine was never meant produce random results? Because I compare results, not engines.

/die cannot be used for standard dice (d2/3/4/6/8/10/20/100) or click based automation.

And the „write an extension“ arguments gets repeated far too often around here. I pay for finished products so that I do not have to do it by myself. This includes adventure paths and extensions.

[Kelrugem]

Ah, of course, this I can do. I left all the explanation out, because if no one at SW was interested in the result and people come „pfff“ and „Blabla“ at me again then by do even more work?!

I am in bed now, but can write that down for you tomorrow after finally playing chess with my daughter (she kept asking).


I thought the visual comparison of FGU creating patterns where others create (TV like) noise was strong and clear that it already proved the main point. I was wrong in that.


I did, but how much more can one do with 1 mio. D8 rolls than what I did and no one here seems to have done before? I decided to offer these only per request, especially after being somewhat ridiculed for doing so many rolls. I also omitted results like average and such, because they were unsuspicious.

There are more randomness tests out there that are harder to use (even more so on Windows) and don‘t seem to produce better result.

Diehard
Dieharder
NIST
TestU01

Cool, thanks (when it does not cause too much stress; I appreciate that someone had the energy to do all of that )

The problem I had with your first graphic was that I didn't see that it is a gif I just read the random.org at its bottom, and I thought you just put some example image of some wiki page as a reference Hence, I didn't realize that there are other images in that part, too

[smelton]

So the physics engine was never meant produce random results?

No actually. It's physics (an approximation at the least).

[smelton]

Because I compare results, not engines.

If you want to really test this out, find another app that uses physics based dice or pick up a d8 and throw it in a dice tray and compare that.