Thanks.  I misunderstood the code and help file for as.svrepdesign().  I thought when you specified large="merge" on brrweights(), it would assign the PSUs within each stratum to 1 of 2 new super PSUs within the stratum.  So if stratum 1 had 7 PSUs, they would each be assigned to super PSU 1 or super PSU 2 in stratum 1.  But now I realize it creates super stratum instead; so if stratum 1 had 1 PSU and stratum 2 had 1 PSU, then large="merge" would assign PSU 1 in stratum 2 to PSU 2 in stratum 1 (and stratum 2 would be dropped).  Or vice versa.  That's very clever.
 
I can renumber the PSUs before sending them to as.svyrepdesign() with type="BRR".
 
Thanks again.

Thomas Lumley <tlumley@u.washington.edu> wrote:
On Mon, 19 Apr 2004, Fred Rohde wrote:

> Is there a way to create a BRR svrepdesign from a survey design when the
> number of PSUs is odd in one or more stratum? Creating a JKn
> svrepdesign with that condition works okay, but when I tried to create a
> svrepdesign with type="BRR" I get an error and this message:
>
> "Can't split with odd numbers of PSUs in a stratum"

Oh dear, how very frustrating, (or words to that effect).
The parameters aren't being passed on to brrweights().

You aren't supposed to be able to split a stratum with an odd number of
clusters, because the result won't be balanced. You are supposed to
be able to merge two strata with an odd number of clusters, but it isn't
working. Note that it should only work when the number of odd strata is
even. BRR is, fundamentally, intended for strata of size 2 and I think
there's something slightly dodgy about attempts to get around this.

-thomas

		
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