The Census Bureau suggests an approximation for calculating standard errors (MOE/1.645)  for estimate differences (see link below).
 
http://www.census.gov/acs/www/Downloads/data_documentation/Statistical_Testing/2009StatisticalTesting3and5year.pdf
The calculation for differences is the same as for aggregations (As Liang noted, the standard error increase whenever you combine estimates regardless of whether you are combining them or differencing them). 
 
Regards to all.

From: Louis Pino <LPino@drcog.org>
To: "ctpp-news@chrispy.net" <ctpp-news@chrispy.net>
Sent: Fri, February 4, 2011 3:54:14 PM
Subject: [CTPP] RE: "Backing out" MOE

Thank you for the replies, but I guess my question was not clear.

I know how to create the MOEs for the aggregated data, but I am wondering how to calculate the MOE when the estimate is derived by taking the difference of the muni totals from the county totals to get the unincorporated piece of the county.


Thanks again,


Louis


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  1. RE: "Backing out" MOE  (Liang.Long@dot.gov)


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Subject: RE: [CTPP] "Backing out" MOE
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