Displaying 2 results from an estimated 2 matches for "86e6".
Did you mean:
86,6
2017 Nov 05
5
Extreme bunching of random values from runif with Mersenne-Twister seed
On 04/11/2017 10:20 PM, Daniel Nordlund wrote:
> Tirthankar,
>
> "random number generators" do not produce random numbers. Any given
> generator produces a fixed sequence of numbers that appear to meet
> various tests of randomness. By picking a seed you enter that sequence
> in a particular place and subsequent numbers in the sequence appear to
> be unrelated.
2017 Nov 05
0
Extreme bunching of random values from runif with Mersenne-Twister seed
...re constructed so that with x_{n+1} = f(x_n),
x_1, x_2, x_3,... will look random, not so that f(s_1), f(s_2), f(s_3), ... will look random for any s_1, s_2, ... . This is true, even if seeds s_1, s_2, ... are not chosen so as to mess with the RNG. In the present case, it seems that the seeds around 86e6 tend to give similar output. On the other hand, it is not _just_ the similarity in magnitude that does it, try e.g.
s <- as.integer(runif(1000000, 86.54e6, 86.98e6))
r <- sapply(s, function(s){set.seed(s); runif(1,17,26)})
plot(s,r, pch=".")
and no obvious pattern emerges. My best...