important: a female who thinks of the principal as a friend but not vice versa (a contact-perceived friend) does not appear to have a significant effect, but the overlapping confidence intervals indicate that the difference in the effect size is not significant. Gender also played a role among spouses. Heavy drinking by a wife increased the likelihood that the husband drank heavily by 196% (95% CI:91% to 329%), whereas heavy drinking by a husband increased the likelihood that a wife drank heavily by 126% (95% CI:67% to 202%). Among siblings the effect was significantly smaller and did not differ whether the contact was a sister (37%, 95% CI:0% to 85%) or a brother (34%, 95% CI:8% to 66%). Immediate neighbors and coworkers did not exhibit any significant effects on a principal's drinking behavior.
