Case Likelihoods Questions

[Captainmajestik]

On Badmephisto's site, it has the likelihoods of each PLL case coming up, and most of them say 1/18. But I don't really think that's exact, because I seem to see the G's and N perms pop up a lot more than it says they should be.

So, are those right?

And as an extension of the above, what perms do you guys see pop up more than most?

 

[Stefan]

So, are those right?

Yes.

And as an extension of the above, what perms do you guys see pop up more than most?

None, cause most pop up equally often (all those with 1/18).

In general, if you can't decide whether math is right or your gut feeling based on your individual experience distorted by biased recall is right... go with math.

 

[Godmil]

I seem to see the G's and N perms pop up a lot more than it says they should be.

Well statistically 2 in 9 solves should be G perms, which is a lot, I'd be suprised if you felt they were even more common than that.

 

[Captainmajestik]

Well, I tend to include G and R's together, because I base it off of how often I have to do A+U, and I don't know the both of those yet. Fortunately, those are the last ones I have left before I know full PLL, so yeah.

 

[Godmil]

Well, I tend to include G and R's together

Yeah, ok, so that's 1 in 3 solves.

 

[applemobile]

I will go a whole day without a G-perm followed by about 5 in a row. True story. Same goes for pll skips, I often get two in a row.

 

[Sa967St]

PLLs with that look different from all sides: 1/18
PLLs with that look the same from 2 sides: 1/36
PLLs with that look the same from all sides: 1/72

And as an extension of the above, what perms do you guys see pop up more than most?

The distribution should be roughly the same as their likelihoods, if you don't purposely affect PLL in any way during OLL. If you remember certain PLLs popping up more than others with the same likelihoods, it's probably because you don't pay enough attention. People tend to only remember things that they choose to remember. Let's say someone whose favourite PLL is J(a) does an average of 100. If he gets about 10 J(a) perms, he'll probably remember that he has lots of J(a) perms, but not realize that he also had about 10 R(a) perms.

Does anyone remember this?
http://www.speedsolving.com/forum/showthread.php?13330-Quick-experiment-need-participants

 

[Stefan]

1) PLLs with no lines of symmetry: 1/18
2) PLLs with horizontal/vertical symmetry, or diagonal symmetry: 1/36
3) PLLs with diagonal symmetry and horizontal/vertical symmetry: 1/72

There are PLLs in both 2) and 3) (because "A and B" is a subset of "A or B").
I'd say T/Y/F/V are in 2) but all have 1/18.
I'd say the Ns are in 1) (*) but they have 1/72.

But I might misunderstand what you mean. Does the "/" in "horizontal/vertical" mean "and", "or" or "combined" or something else?

(*) As in they have no "line" of symmetry. They do have *rotational* symmetry which is the real reason for the differing probabilities.

 

[Sa967St]

But I might misunderstand what you mean. Does the "/" in "horizontal/vertical" mean "and", "or" or "combined" or something else?

Nah, I just failed at explaining. I think my post makes more sense now.

 

[Foster Conklin]

I tend to get a lot of G perms too. I think that is because there are four G cases, so they should occur four times as often. That's always been my perception of it, correct me if I am wrong.