[gurps] declining probability

[Captain Joy]

On Monday, June 18, 2007, at 10:48  PM, Max, Dunedin, NZ wrote:
> Captain Joy wrote:
>> Here is what I came up with:
>>     Avg # or rolls to till you hit 0 given a starting no. to beat
>> 3    3.0046511628
>> 4    4.0235190873
>> 5    5.0720627766
>> 6    6.174103593
>> 7    7.3674737587
>> 8    8.7174737587
>> 9    10.317473759
>> 10    12.317473759
>> 11    14.984140425
>> 12    18.841283283
>> 13    25.012711854
>> 14    35.812711854
>> 15    57.412711854
>> 16    111.41271185
>> 17    327.41271185
>> 18    infinite
>
> Just one note, it won't make to much difference to the results, but as 
> this is GURPS, the statistics are slightly different, ie a 17 & a 18 
> are always a failure, which means 18 won't be infinite.

Oh, you're right about that.  Well, given that 17 and 18 are always 
failures, then the results for 17 and 18 will be exactly the same as 
for 16.

Also, going from 10 to 0 in only 12 rolls didn't seem right to me, so I 
did thirty trials on a spreadsheet.  The average came to 10.4, so I 
guess 12 isn't too low.
--
captainjoy at mac.com
"It's life, Captain, but not life as we know it." --Commander Spock