## Support #869

### Unexpectedly strong gender homophily in Understanding Society compared with the BHPS

100%

**Description**

# Summary¶

I am interested in homophily effects that can be derived from the social network questions in waves B, D, F, H, J, L, N, P, R of the BHPS and waves C and F of Understanding Society. Homophily with respect to occupational status is relatively constant across all waves, and age homophily only changes slightly. However, homophily with respect to gender increases sharply from the last wave of the BHPS (R) to the first wave of Understanding Society (C). Do you happen to have any ideas whether a data error (or misuse on my part) might cause such an effect?

# Details and code for reproducing the observations¶

For each wave of the survey I compute the contingency table of the sex of the ego (respondent) and alter (nominated friend) and apply the Fisher exact test (https://en.wikipedia.org/wiki/Fisher%27s_exact_test) to compute the odds ratio of association and test for statistical significance.

To account for effects of the survey design I use the weight

#xrwghtfor the BHPS and

#_indscub_xwfor Understanding Society (the results are similar when omitting the survey weights). The results below include survey weights but the contingency tables have been rounded to the nearest integer. The code to reproduce the results can be found here: https://gist.github.com/tillahoffmann/e48dbc3546c418561263d181b2bda694

Thank you very much for your help!

BHPS wave: b Contingency table [[ 8862 3011] [ 2202 11176]] Odds ratio: 14.947, p-value: 0.000000 BHPS wave: d Contingency table [[ 8435 2817] [ 2053 11044]] Odds ratio: 16.116, p-value: 0.000000 BHPS wave: f Contingency table [[ 8500 3253] [ 2195 11149]] Odds ratio: 13.277, p-value: 0.000000 BHPS wave: h Contingency table [[ 8328 3034] [ 1980 10994]] Odds ratio: 15.249, p-value: 0.000000 BHPS wave: j Contingency table [[ 7936 2935] [ 1941 10541]] Odds ratio: 14.697, p-value: 0.000000 BHPS wave: l Contingency table [[ 7625 2791] [ 1888 10157]] Odds ratio: 14.696, p-value: 0.000000 BHPS wave: n Contingency table [[7320 2663] [1827 9780]] Odds ratio: 14.713, p-value: 0.000000 BHPS wave: p Contingency table [[7099 2597] [1714 9436]] Odds ratio: 15.052, p-value: 0.000000 BHPS wave: r Contingency table [[ 7682 2910] [ 1964 10312]] Odds ratio: 13.865, p-value: 0.000000 Understanding Society wave: c Contingency table [[36818 9400] [ 6777 44476]] Odds ratio: 25.710, p-value: 0.000000 Understanding Society wave: f Contingency table [[30372 7348] [ 5004 36279]] Odds ratio: 29.972, p-value: 0.000000

#### Updated by Stephanie Auty about 3 years ago

**Category**set to*Data analysis***Status**changed from*New*to*In Progress***Assignee**set to*Stephanie Auty***% Done**changed from*0*to*10***Private**changed from*Yes*to*No*

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.

Best wishes,

Stephanie Auty - Understanding Society User Support Office

#### Updated by Stephanie Auty about 3 years ago

**Status**changed from*In Progress*to*Feedback***Assignee**changed from*Stephanie Auty*to*Till Hoffmann***% Done**changed from*10*to*80*

Dear Till,

There are several differences in the way these questions were asked from Wave 18 of the BHPS to Wave 3 of Understanding Society.

1. In Understanding Society, these questions are only asked if the respondent says they have more than one close friend. In the BHPS there is no such filtering and so they are not allowed to say they don’t have any close friends. As a result this could lead to someone in the BHPS answering about people they would not count at ‘close’ friends.

2. In the BHPS the question specifies that the friends to whom these questions refer should not live with the respondent but could be a relative. In Understanding Society, there is no such restriction.

3. Also, note that you are using weights which are specific to the self-completion section in Understanding Society, but in BHPS there are no self-completion weights.

4. In Understanding Society, a much higher proportion of the sample are ethnic minorities as compared to the BHPS sample. Even if you use weights which should correct for the over-sample of ethnic minorities in the UKHLS, UKHLS and the BHPS represent different populations (1990 Vs 2009/10). If these populations have different propensities of having same-gendered friends, then there may be differences.

Best wishes,

Stephanie Auty - Understanding Society User Support Officer

#### Updated by Stephanie Auty about 3 years ago

**Status**changed from*Feedback*to*Resolved***% Done**changed from*80*to*100*