Parameter definitions
| Parameter | Definition | Values used |
|---|---|---|
| *Obtained from maximum likelihood estimation (fig 2). | ||
| μ | Entry rate | 0.1 per year (average length of stay in |
| To maintain a constant population size, the entry and exit rates are assumed to be equal | model population 10 years, population aged 16–25 years) | |
| βk | Transmission probability of infection to sex k per contact23 | Probability per contact* |
| Best fit 0.4 (male to female) | ||
| Best fit 0.6 (female to male) | ||
| δk, | Recovery rate from infection23 | Best fit 2 months (male and female)* |
| Pklmst | Mixing matrix, element ρklmst gives the probability that an individual of sex k in activity class l, ethnicity s, will form a partnership with a member of activity class m and ethnicity t (opposite sex, k′) | See below |
| Calculated in simulation | ||
| χkls | Partnership formation rate of individual of sex k, activity class l, ethnicity s (see below) | See below |
| Calculated from sexual behaviour survey—table 4 | ||
| ε1, ε2 | Pattern of mixing | Mixing by activity class varied from 0⩽ε21 |
| (0 = fully assortative, 1 = random) | Ethnicity mixing (ε1 defined explicitly in equation) | |