Understanding Society User Support

Dear Freya,

Thank you for your question. I am not sure how long back you are looking at. But overall, you are right in using the cross-sectional weight that is most inclusive. You can use us weight for wave 1 of UKHLS, ub weight between wave 2 and wave 5, and ui weight starting at wave 6 onwards. If you are looking back at BHPS, you can use cross-sectional weights as well. But overall please be aware of the differences in the population that the data represents. For example us weight represents people who lived in the UK continuously since 2007/2008 (excluding immigrants that came to the country since). But ui weight represents people who lived in the UK continuously since 2012/2013. You may see the jump therefore in your estimates over time between wave 5 and wave 6 estimates (which use su and ui weights). If so, it may be better to use us or ub weight consistently - this will exclude more recent immigrants. If you don't see any jump, then immigrants do not influence your estimates so much - and you may continue to use us, ub and ui weights when appropriate.

Hope this helps,
Olena

Dear Olena
Many thanks for your very helpful email. I have a follow-on question which relates to how I use the chosen weight in my logistic regression analyses which I am carrying out using STATA. I am currently specifying the weight using the syntax:
logistic h_finnow ib1.h_age_dv [ pw= h_indpxui_xw ] , base vce(cluster h_hidp)

This allows for the weighting and clustering by household (h_hidp). However, I do not think it correctly estimates the standard errors. I am wondering if I need to use the svy commands instead? My understanding is that this will provide an appropriate (and larger) estimate of the standard errors. Thus I am proposing to use:

svyset h_ppid [pw=h_indpxui_xw] || h_hidp
svy: logistic h_finnow ib1.h_age_dv , base

Many thanks

Freya Cook

Freya,

Yes, svy command is better suited for your purpose. This style of svyset command may be better, and also include strata in your analysis:
svyset psu [pweight=pw], strata(strata)

And then use logistic regression with svy:

Does this help? There are more examples in UKHLS training course materials.
Olena