Predicted purchase rates under modelled hypothetical conditions (%, 95% confidence intervals)
| If minors carried ID … | ||||
|---|---|---|---|---|
| Always | Random half of cases | Never | ||
| Always | 11.5 (10.8 to 12.1) | 7.6 (7.0 to 8.1) | 3.7 (3.5 to 4.0) | |
| If clerks asked ID … | 87% of cases (rate in experiment) | 17.7 (16.3 to 19.0) | 13.0 (11.8 to 14.2) | 8.1 (7.2 to 9.0) |
| Random half of cases | 34.0 (32.3 to 35.7) | 21.4 (20.2 to 22.5) | 17.5 (16.3 to 18.7) | |