Proposal: Regulations to ensure scrambling accuraccy

[BaMiao]

I don't think you can make this presumption. I'm not sure I agree, actually.

It seems to have been the prevailing opinion. Besides, do you think the scrambles shouldn't matter? Also, remember that there have been examples of solves thrown out due to mis-scramble (like with Nathan Soria). Wouldn't it have been nice if he had an additional solve?

WRC has no input in these decisions.

Sorry, I guess I'm getting my committees mixed up. Is it the board who makes these decisions?

 

[Julian]

It seems to have been the prevailing opinion.

Fine, but you said everyone.

Besides, do you think the scrambles shouldn't matter? Also, remember that there have been examples of solves thrown out due to mis-scramble (like with Nathan Soria).Wouldn't it have been nice if he had an additional solve?

That's different, Nathan's was DNF'd because the optimal solution was <7.

 

[MrMan]

I will begin my informatic studies next year, I already have some experience and more importantly the two first years will leave me a lot of free time.
So I will try to develop an app for smartphone if nobody does it. It will be a great experience for my studies.

 

[Myachii]

What are the chances of the scrambler looking only at the white face and seeing it is exactly correct to the scramble yet the scramble being incorrect?

Just curious..

 

[MaeLSTRoM]

What are the chances of the scrambler looking only at the white face and seeing it is exactly correct to the scramble yet the scramble being incorrect?

Just curious..

Pretty high. If you assume that the white face has not only the correct stickers, but the correct pieces, then the chance of the rest of the cube being correct is:
1 in (2^7 * 8! * 3^3 * 4! * (1/2)) = 1 in 1672151040 (1.67x10^9, full cube has 43x10^18 possibilities for reference)
If you're only checking stickers, then its even higher


TL;DR, pretty damn low.

 

[irontwig]

Well, that way of calculating makes a ton of sense, doesn't it? Oh, wait. Better phrased: what's the probability of apostrophe being missed (this can be approximated with a random 2+2C2+2E switch) , but the white face being identical with the right scramble?

 

[rokicki]

Pretty high. If you assume that the white face has not only the correct stickers, but the correct pieces, then the chance of the rest of the cube being correct is:
1 in (2^7 * 8! * 3^3 * 4! * (1/2)) = 1 in 1672151040 (1.67x10^9, full cube has 43x10^18 possibilities for reference)
If you're only checking stickers, then its even higher


TL;DR, pretty damn low.

In practice, the chances are much higher than this. Consider the possibility that the scramble ends in
a clockwise move of the yellow face, and the scrambler accidentally twists this face counterclockwise.
This single case alone is much more probable than the value given above. Yet there are many
additional errors that will end with the white face correct.

Any single error in a scramble (inserting a move, omitting a move, or making a move incorrectly)
will cause exactly four edges and four corners to be wrong. If we use this as our model of errors,
we might be able to come up with a much more realistic estimate---and I believe the result will be
too high for our purposes.

Likely we need to check two opposite faces to gain enough confidence. And even that can probably
be "defeated" by a determined adversary.

 

[MaeLSTRoM]

Just to be clear, I wasn't trying to make any kind of statement about chances of mistakes overall, just answering the question stated exactly as it was asked.

 

[irontwig]

So you were just answering a meaningless question that has nothing to this with the topic of this thread? Good.

 

[Mollerz]

So you were just answering a meaningless question that has nothing to this with the topic of this thread? Good.

No he was answering a question someone asked somewhat relating to the topic.

 

[kinch2002]

Sorry, I guess I'm getting my committees mixed up. Is it the board who makes these decisions?

The WRC deals with the regulations (e.g. wording of, interpretation of etc).
The Board would make any final decisions in situations that require debate unless if falls under the remit of...
The WDC deal with disciplinary action (although their final recommendations/actions are approved by the Board)