Hi all
I hope everyone is healthy.
If we want to combine categories within a table, what’s the most appropriate way to calculate margin of error or coefficient of variation?
So for example, if we want to look at children in poverty, by race/ethnicity, by county, and were using the b17020 series, for example, b17020b, and wanted to get “children” under 18, we’d have to combine three groups, “under 6”, “6 to 11” and “12 to 17”. What’s the best way to calculate margin of error or coefficient of variation for “children”?
https://data.census.gov/table?q=b17020b&g=0400000US36$0500000&tid=ACSDT5Y2021.B17020B
A couple of presentations / documents seem to explain how to do it. Are these what we’d use? I just want to check these are the most recent and would still be used.
Calculating Margins of Error the ACS Way Using Replicate Methodology to Calculate Uncertainty
https://www2.census.gov/about/training-workshops/2020/2020-02-12-acs-presentation.pdf
Worked Examples for Approximating Margins of Error. Instructions for Applying Statistical Testing
https://www.census.gov/programs-surveys/acs/technical-documentation/code-lists.html
Thanks
Gene
Gene,
Those are the right resources. You can use the Census Bureau's worked examples to approximate margins of error for your derived estimates. If you're using 5-year data you could also get more accurate MOEs for derived estimates by using the Variance Replicate Estimates (VRE) Tables, which use replicate weights. The VRE tables for the 2017-2021 ACS data have not been released yet but should be available on Jan. 23.
The Census presentation you cite does a nice job of explaining how to use the VRE tables if you decided to go that route.