Create multinomial distribution for infection probabilities

infection_probabilities(multi_dens, params)

Arguments

multi_dens	Matrix where each row gives the probability density of each infection type for a given multiplicity of infection.
params	Parameter vector. Must contain at least one value named `mu`, which is the mean muliplicity of infection. Could also contain `size` in which case negative binomial distribution is used. See details.

Value

Returns a named multinomial probability distribution.

Details

Using either a poisson or negative binomial distribution, the probability of drawing `1:nrow(multi_dens)` for the parmeters provided is calculated. These are used as weights to then calculate the weighted mean probability of each infection type (the columns in `multi_dens`).

Examples

if (FALSE) {

# create our arguments
multi_dens <- matrix(c(0.5,0.3,0.2,0,0,0,0,
                       0.25,0.09,0.04,0.3,0.2,0.12,0),
                        nrow = 2,byrow=TRUE)
colnames(multi_dens) <- c("a", "b", "c", "a/b", "a/c", "b/c", "a/b/c")

# first calculating using a poisson
params <- c("mu" = 2)
infection_probabilities(multi_dens, params)
#>     a     b     c   a/b   a/c   b/c a/b/c
#> 0.375 0.195 0.120 0.150 0.100 0.060 0.000

# no using the negative binomial
params <- c("mu" = 2, "size" = 1)
infection_probabilities(multi_dens, params)
#>     a     b     c   a/b   a/c   b/c a/b/c
#> 0.400 0.216 0.136 0.120 0.080 0.048 0.000

}