Convert a contact matrix to per-capita rates

Divides each column of the contact matrix by the population of the corresponding age group, giving the contact rate of age group i with one individual of age group j.

Usage

per_capita(x, survey_pop, ...)

Arguments

x

a list as returned by compute_matrix(), with elements matrix and participants

survey_pop

a data frame with columns lower.age.limit and population (e.g. from wpp_age())

...

passed to pop_age() for interpolation

Value

x with $matrix replaced by the per-capita version

Examples

data(polymod)
pop <- wpp_age("United Kingdom", 2005)
#> Warning: `wpp_age()` was deprecated in socialmixr 0.6.0.
#> Pass population data directly via the {.arg survey_pop} argument instead.
#> ℹ The underlying {.pkg wpp2017} data is also outdated; use {.pkg wpp2024} from
#>   GitHub for more recent data.
polymod |>
  (\(s) s[country == "United Kingdom"])() |>
  assign_age_groups(age_limits = c(0, 5, 15)) |>
  compute_matrix() |>
  per_capita(survey_pop = pop)
#> 
#> ── Contact matrix (3 age groups) ──
#> 
#> Ages: "[0,5)", "[5,15)", and "[15,Inf)"
#> Participants: 1011
#> 
#>           contact.age.group
#> age.group         [0,5)       [5,15)     [15,Inf)
#>   [0,5)    5.547112e-07 1.938376e-07 1.117610e-07
#>   [5,15)   1.532896e-07 1.075909e-06 1.257024e-07
#>   [15,Inf) 1.130535e-07 1.747666e-07 1.940255e-07