> Some of the random number generators allow as a seed a vector, > not only a single number. This can simplify generating the seeds. > There can be one seed for each of the 1000 runs and then, > the rows of the seed matrix can be > > c(seed1, 1), c(seed1, 2), ... > c(seed2, 1), c(seed2, 2), ... > c(seed3, 1), c(seed3, 2), ... > ... > > There could be even only one seed and the matrix can be generated as > > c(seed, 1, 1), c(seed, 1, 2), ... > c(seed, 2, 1), c(seed, 2, 2), ... > c(seed, 3, 1), c(seed, 3, 2), ... > > If the initialization using the vector c(seed, i, j) is done > with a good quality hash function, the runs will be independent. > > What is your opinion on this? > > An advantage of seeding with a vector is also that there can > be significantly more initial states of the generator among > which we select by the seed than 2^32, which is the maximum > for a single integer seed. > >
Hello, I would be also in favor for using multiple seeds based on (seed, task_number) for convenience (i.e. avoiding storing the seeds) and with the possibility of having a dynamic number of tasks, but I am mot sure it is theoretically correct. But I can refer you to this article: http://www.agner.org/random/ran-instructions.pdf , section 6.1 where the author states: For example, if we make 100 streams of 10^10 random numbers each from an > SFMT > generator with cycle length Ï = 2^11213, we have a probability of overlap > p â 10^3362. > What do you think ? I am very concerned by the correctness of this approach so would appreciate any advice on that matter. Thanks Karl [[alternative HTML version deleted]]
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