Re: [R] R2WinBUGS results not different with different runs
Gregor Gorjanc wrote: toby909 at gmail.com writes: Is this a specialty with R2WinBUGS? Does it have something to do with the seed value? Isnt the seed value reset everytime I restart winbugs? I always have the same seed if I start WinBUGS multiple times. So you get exactly the same chain, numerically, when rerunning the same model, with the same number of iterations, everything the same.? Wouldnt that be problematic if every researcher in the world who uses winbugs uses the same sequence of random numbers? R's random numbers are different each time, because the seed is linked to the clock in your PC. T Gregor __ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. __ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
Re: [R] R2WinBUGS results not different with different runs
toby909 at gmail.com writes: Gregor Gorjanc wrote: toby909 at gmail.com writes: Is this a specialty with R2WinBUGS? Does it have something to do with the seed value? Isnt the seed value reset everytime I restart winbugs? I always have the same seed if I start WinBUGS multiple times. So you get exactly the same chain, numerically, when rerunning the same model, with the same number of iterations, everything the same.? I just tried now with Gelman's schools example from bugs() help page. I runned the same job twice, with exactly the same initial values. Notes that WinBUGS uses always the same starting seed. I got this schools.sim$last.values [[1]] [[1]]$theta [1] 23.700 10.060 12.760 13.090 1.693 14.390 7.599 3.961 [[1]]$mu.theta [1] 25.03 [[1]]$sigma.theta [1] 20.08 schools.sim2$last.values [[1]] [[1]]$theta [1] 23.700 10.060 12.760 13.090 1.693 14.390 7.599 3.961 [[1]]$mu.theta [1] 25.03 [[1]]$sigma.theta [1] 20.08 Wouldnt that be problematic if every researcher in the world who uses winbugs uses the same sequence of random numbers? R's random numbers are different each time, because the seed is linked to the clock in your PC. You can reset the seed if you want. Having the same seed is also nice for repeatability. Gregor __ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
Re: [R] R2WinBUGS results not different with different runs
toby909 at gmail.com writes: Is this a specialty with R2WinBUGS? Does it have something to do with the seed value? Isnt the seed value reset everytime I restart winbugs? I always have the same seed if I start WinBUGS multiple times. Gregor __ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
