Message text written by INTERNET:Richard.W.Nichols@travelers.com
>Its been years since I used APL, but back in the early 1980's I used to =
do
a
class on APL where I would demonstrate the random number generator to pic=
k
lotto
numbers. I would write them down on the board after showing the APL
statement
that generated them. Later in the class I would run the same APL
statement,
and, magically, get the same answer. The point of the exercise was to
demonstrate that the random number generator in APL always started with t=
he
same
seed if you started in a newly opened workspace. Starting with the same
seed
meant that APL would generate the same random numbers in the same order
every
time. (Anyone know if this is still true?)
We warned the actuarial students taking the class to be sure to randomize=
the
seed, either by always saving the workspace after each simulation so that=
the
new seed would be saved as well, or by using the clock to randomize the
seed.
We would simply pick N random numbers where N was the number of
milliseconds on
the current time.
All this did nothing to fix any bias that may have been in the RNG, but i=
t
shows
that there may be other problems as well. Anyone know if you can reset t=
he
seed
in Excel?
Rich<
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