RE: [Bug-gnubg] rollout settings

[nis]

On 29 Oct 2002 at 9:01, Ian Shaw wrote:

> There has been some discussion about what happens if you do a rollout of <
> 1296 trials with rotation enabled. If the rolls are not random, you might
> skew the results if you do less than 1296 trials because, for example, you
> miss all sequences where X rolls 66.

This won't happen. The only problem we know of is that the "temporary 
results" shown during the rollout, or if you terminate it before it 
finishes - those can be skewed.

> There was some discussion about randomising the rolls within the 1296
> sequence, but this has not been implemented yet as far as I know.

True

> Until I understand what's happening, I don't trust rollouts using rotation
> unless there are at least 1296 trials.

You can trust them.

> Can anyone verify the current state of play:
> 
> What happens if trials < 1296?

At most the first roll is rotated

> What happens if trails = 36n where 1 <= n <= 36?

The first roll is rotated

> Are trials after 1296 random or does the rotation restart? Do we need to
> do 1296n trails to avoid skew?

If trials are not a multiplum of 1296, at most the first roll is 
rotated.

In general, for n<=4, the n'th roll is rotated if and only if  trials 
is a multiplum of 36^n-- 
Nis Jorgensen
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