[R] Simulation Function - Save results

[David Winsemius]

On Aug 17, 2009, at 1:40 PM, MarcioRibeiro wrote:

>
> Ok, the LIST function I understood...

I didn't see how you got a "random" input to that function. Would seem  
to need one of the r<dist> functions as input.

> What I would like now is to simulate this Function A many times (S)  
> in order
> to get S results for the MEAN and for the VARIANCE...


?replicate

>
>
> Zhiliang Ma wrote:
>>
>> in order to return more multiple variables, you can put them in a  
>> list
>> and then return this list.
>>
>> e.g.
>>
>> #Function A
>> boot<-function(a,b,c){
>> mean_boot<-(a+b)/2
>> var_boot<-c
>>
>> list(mean_boot = mean_boot, var_boot = var_boot)
>> }
>>
>> out <- boot(1,2,3)
>> out
>> $mean_boot
>> [1] 1.5
>>
>> $var_boot
>> [1] 3
>>
>>
>>
>> On Fri, Aug 14, 2009 at 1:15 PM, MarcioRibeiro<mestat at pop.com.br>  
>> wrote:
>>>
>>> Hi listers,
>>> I am working on a simulation... But I am having some troubles...
>>> Suppose I have a function A which produces two results (mean and
>>> variance)...
>>> Then I would like to simulate this function A with a function B many
>>> times
>>> using the results from function A
>>> For example:
>>>
>>> #Function A
>>> boot<-function(a,b,c){
>>> mean_boot<-(a+b)/2
>>> var_boot<-c
>>> #list(a=a,b=b,c=c)
>>> return(a)
>>> }
>>>
>>> Then I would like to create 2 vectors with the mean and var  
>>> results from
>>> S
>>> simulations
>>>
>>> #Function B
>>> simul<-function(S){
>>> teste<-rep(0,S)
>>> for(i in 1:S){
>>> teste[i]<-boot(10,12,15)  #ACCORDING TO FUNCTION A I AM SAVING  
>>> JUST THE
>>> MEAN_BOOT, BUT I ALSO NEED THE RESULT OF VAR_BOOT
>>> }
>>> var<-var(teste)
>>> mean_emp<-mean(var_boot) #THIS IS NOT WORKING, BECAUSE I DONT HAVE  
>>> THE
>>> VAR_BOOT AT MY VECTOR
>>> var_emp<-(sum((var_boot-var)**2))/S #THIS IS NOT WORKING, BECAUSE  
>>> I DONT
>>> HAVE THE VAR_BOOT AT MY VECTOR
>>> }
>>> simul(5)
>>>
>>> But my problem is that I don't know how to save my results in 2  
>>> vectors
>>> in
>>> order to use then at function B.
>>> Thanks in advance,
>>> Marcio
>>>
>>> --
>>> View this message in context:
>>> http://www.nabble.com/Simulation-Function---Save-results-tp24977851p24977851.html
>>> Sent from the R help mailing list archive at Nabble.com.
>>>
>>> ______________________________________________
>>> R-help at r-project.org 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 at r-project.org 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.
>>
>>
>
> -- 
> View this message in context: http://www.nabble.com/Simulation-Function---Save-results-tp24977851p25011101.html
> Sent from the R help mailing list archive at Nabble.com.
>
> ______________________________________________
> R-help at r-project.org 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.

David Winsemius, MD
Heritage Laboratories
West Hartford, CT