Benoit Dulong
>
> Consider n balls: #1, #2, ..., #n.
> I draw k balls at random, WITHOUT replacement.
> The result is noted x1, x2,...,xk.
> I want to repeat this r times.
> The data file should be: r lines and k colomns.
>
> How can I generate this data file?
> Where should I look?
>
> I looked at STB-28: sg44; STB-41: sg44.1, rnd.
>
> I am trying to knit my own program...
I'd generate this as a one long composite sample,
and then -reshape-.
Suppose n = 10 , k = 6, r = 100. Then we need n * r
observations:
set obs 1000
We set up ids:
egen sample = seq(), b(10)
egen ball = seq(), t(10)
If desired,
set seed 123456789
Get random numbers
gen random = uniform()
Shuffle randomly within each sample:
sort sample random
We only want 6:
by sample : keep if _n <= 6
And -reshape-:
drop random
by sample : gen id = _n
reshape wide ball , j(id) i(sample)
Nick
[email protected]
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