[R] Problem with random numbers/seed

Steven Yen @tyen @end|ng |rom ntu@edu@tw
Fri Jun 21 19:09:28 CEST 2019


Now I see that results were replicated but running RNGversion
I get a warning message. Isn't there a way to do this clean?

> RNGversion("3.5.3") Warning message: In RNGkind("Mersenne-Twister", 
"Inversion", "Rounding") : non-uniform 'Rounding' sampler used


On 6/22/2019 1:03 AM, Uwe Ligges wrote:
> What does not work?
>
>
> For me it works under R-3.6.0:
>
>  x<-1:500
>  set.seed(12345671)
>  j<-sample(1:length(x),size=60); y<-x[j]
>  summary(j)
>
>  RNGversion("3.5.3")
>  set.seed(12345671)
>  j<-sample(1:length(x),size=60); y<-x[j]
>  summary(j)
>
>
> Now I get the results you got udner the old R.
>
> Best,
> Uwe Ligges
>
>
>
> On 21.06.2019 18:39, Steven Yen wrote:
>> Thanks. Somewhat of a mystery. The older version I had was 
>> R-3.5.3patched.
>> I cannot get the RNGversion command to run. Can you help? Thanks.
>>
>> On 6/22/2019 12:25 AM, Uwe Ligges wrote:
>>> See the NEWS, the RNG has been changed, use RNGversion
>>>
>>> On 21.06.2019 18:10, Steven Yen wrote:
>>>> Dear all,
>>>> I did all this work with older R (R-3.5.3.patched and older)
>>>> but now with R3.6 I cannot replicate the results.
>>>> Below I sample 60 observations from 1:500 using the sample command 
>>>> with
>>>> a random seed of 123. I get different results. Advice appreciated.
>>>> Steven Yen
>>>>
>>>>   > # Run under R-3.6.0
>>>>   > x<-1:500
>>>>   > set.seed(12345671)
>>>>   > j<-sample(1:length(x),size=60); y<-x[j]
>>>>   > summary(y)
>>>>      Min. 1st Qu.  Median    Mean 3rd Qu.    Max.
>>>>      26.0   134.2   240.0   249.8   368.0   500.0
>>>>
>>>>   > # Run under R-3.5.3.patched
>>>>   > x<-1:500
>>>>   > set.seed(12345671)
>>>>   > j<-sample(1:length(x),size=60); y<-x[j]
>>>>   > summary(y)
>>>>      Min. 1st Qu.  Median    Mean 3rd Qu.    Max.
>>>>       9.0   122.2   205.0   236.1   364.2   493.0
>>>>
>>>
>>>
>>> Under R-3.6.0  use, e.g.
>>> RNGversion("3.5.2")
>>> to get reproducible results from the older RNG.
>>>
>>> Best,
>>> Uwe Ligges
>>>
>>>
>>
>> -- 
>> styen using ntu.edu.tw  (S.T. Yen)
>>
>

-- 
styen using ntu.edu.tw (S.T. Yen)


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