Support #1653

Representativeness of lone mothers

Added by Tom Waters 8 months ago. Updated 4 months ago.

Survey design
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I have been comparing the UKHLS data to data from the FRS and LFS. For reasons not clear to me, the UKHLS data seem to be very significantly different when looking at lone mothers.

I attach two .do files which calculate the share of lone mothers that are homeowners, and the age that lone mothers finished education, in both the FRS and UKHLS (for 2009-10 data in FRS, and wave A in UKHLS). It should run if you simply change the "path" global at the top to specify where FRS/UKHLS data are saved.

The results are very different. In the FRS, 16% of lone mothers finished full time education aged 19 or older, and 35% own their own home. In UKHLS those figures are 32% and 47% respectively.

I have tried a number of variations:
  • These differences hold in other years/waves too
  • The differences persist if you do not weight the data
  • The LFS gives figures very similar to FRS, not UKHLS
  • If you look at the whole population (rather than just lone mothers), the two surveys are pretty similar for homeownership, but there is still a much higher rate of leaving education at 19 or later in UKHLS
  • Similar differences seem to hold for lone mothers for other outcomes, including employment (higher in UKHLS) and the take-up of out-of-work benefits (lower in UKHLS)

Very grateful for any guidance in what might be going on here.

Files (1 KB) Tom Waters, 02/07/2022 10:27 AM (801 Bytes) Tom Waters, 02/07/2022 10:27 AM

Updated by Understanding Society User Support Team 8 months ago

  • Category set to Data inconsistency
  • Status changed from New to In Progress
  • % Done changed from 0 to 10

Many thanks for your enquiry. The Understanding Society team is looking into it and we will get back to you as soon as we can.

We aim to respond to simple queries within 48 hours and more complex issues within 7 working days. While we will aim to keep to this response times due to the current coronavirus (COVID-19) related situation it may take us longer to respond.

Best wishes,
Understanding Society User Support Team


Updated by Understanding Society User Support Team 8 months ago

  • Private changed from Yes to No

Updated by Understanding Society User Support Team 8 months ago

  • Assignee set to Understanding Society User Support Team

Updated by Olena Kaminska 8 months ago


Thank you for sharing this with us. We are aware of this general discrepancy. It can have a few different causes, one of which is comparability of the populations that you study. UKHLS being a longitudinal study does not cover recent immigrants (since wave 6) - so in order to better compare you may want to exclude these from other studies too. Also, UKHLS did not sample in institutions at wave 1 - so if your lone mothers lived in student halls in 2009-2010 they may not be in UKHLS. If mothers lived in residential homes at that time and moved into student halls later this would not be a problem. If you can make the datasets more comparable by excluding these subgroups from other datasets, it is possible you would still have some discrepancy left.
We are aware of it, and we have looked at different solutions, but as it's seems to be a case of NMAR we haven't found a perfect solution just yet. While the research continues, I would like to thank you for sending us the detailed description of this problem. We were not aware of this specific influence on lone mothers, so this will be now taken into consideration.

Thank you,


Updated by Understanding Society User Support Team 8 months ago

  • Status changed from In Progress to Feedback
  • % Done changed from 10 to 50

Updated by Understanding Society User Support Team 4 months ago

  • Category changed from Data inconsistency to Survey design
  • % Done changed from 50 to 100

Updated by Understanding Society User Support Team 4 months ago

  • Status changed from Feedback to Resolved

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