# [R] Monte Carlo Simulation

MacQueen, Don macqueen1 at llnl.gov
Sat Apr 16 00:32:59 CEST 2011

```The filenames can be done within a loop, like this:

for (id in 1:1000) {
## the filename
fname <- paste('sample', formatC(id,width=4,flag='0'),'.tsv',sep='')

## more stuff
}

-Don

--
Don MacQueen

Lawrence Livermore National Laboratory
7000 East Ave., L-627
Livermore, CA 94550
925-423-1062

-----Original Message-----
From: Shane Phillips <SPhillips at Lexington1.net>
Date: Fri, 15 Apr 2011 11:49:48 -0700
To: "r-help at r-project.org" <r-help at r-project.org>
Subject: [R] Monte Carlo Simulation

>Hello, R friends...
>
>I am very new to R, and I need some help.  I am trying to construct a
>simulation for my dissertation.
>
>I need to create 1000 datasets of 1000 subjects with the following
>variables...
>
>Treatment variable - Drawn from a binomial distribution (1 run, prob=.13)
>Covariate 1 - Drawn from a normal distribution (mean=100, sd=16)
>Covariate 2 - Drawn from a normal distribution (mean=200, sd=9)
>Covariates 1 and 2 need to be correlated (say, r=.80)
>Covariate 3 - Drawn from a binomial distribution (1 run, prob=.5)
>Covariate 4 - Drawn from a distribution of discrete variables where 1 has
>an 80% chance of being selected, 2  - 10%, 3 - 5% and 4 - 5%.  This
>variable would need to be recoded into 4 binary variables.
>Covariate 5 - Drawn from a normal distribution (mean=84, sd=2)
>Covariate 6 - Drawn from a binomial distribution (1 run, prob=.15)
>Covariate 6 needs to correlate with Covariate 2 (r=.70, or so)
>
>I need each dataset saved as a new datafile with an iterative filename
>(e.g. sample1, sample2, etc.).
>
>
>Thanks!
>
>Shane
>
>______________________________________________
>R-help at r-project.org mailing list
>https://stat.ethz.ch/mailman/listinfo/r-help