# HHWT or PERWT for Derived Families

**URL:** <https://forum.ipums.org/t/hhwt-or-perwt-for-derived-families/510>\
**Category:** USA\
**Created:** [April 29, 2014, 2:44am UTC](https://forum.ipums.org/t/hhwt-or-perwt-for-derived-families/510 "2014-04-29T02:44:00Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![BBett](https://avatars.discourse-cdn.com/v4/letter/b/97f17d/32.png) [@BBett](https://forum.ipums.org/u/BBett)\
**Post date:** [April 29, 2014, 2:44am UTC](https://forum.ipums.org/t/hhwt-or-perwt-for-derived-families/510/1 "2014-04-29T02:44:00Z")

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I am doing a parity analysis, so I’m looking at counts of newborn babies, divided up depending on previous births to that mother (in the household). For example, how many babies were born to a mother that already has one son? one daughter? A son then a daughter? etc.

So while I am counting the individuals, they’ve been formed into family units that might be more similar to households.

I am using the 2007-2011 ACS 1-year data.

In this case should I be using the baby’s weight, the mother’s or the households?

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**Author:** ![grover](https://sea1.discourse-cdn.com/flex019/user_avatar/forum.ipums.org/grover/32/5_2.png) [@grover](https://forum.ipums.org/u/grover)\
**Post date:** [April 29, 2014, 4:08pm UTC](https://forum.ipums.org/t/hhwt-or-perwt-for-derived-families/510/2 "2014-04-29T16:08:00Z")

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Since there is no specific weight associated with families, it primarily up to the researcher to decided which weight to use. According to [Chapter 11](http://www.census.gov/acs/www/Downloads/survey_methodology/Chapter_11_RevisedDec2010.pdf) of the ACS Methodology page, the Census Bureau uses Housing Unit Weights for family-level estimates. I would recommend looking into other family-based research using ACS data to see if there is a common approach in your field.

I hope this helps.