In ramp.xds exposure to infective bites
is handled in several steps:
The number of infective bites, per patch, is computed by a
function F_fqZ.
These bites are allocated to the local human population strata
and to visitors according to their availability, which returns
the daily EIR as a vector. Whereas F_fqz is a
vector of length
or nPatches, the EIR is a vector of length
or nStrata.
Total exposure is transformed into a measure of the local FoI or AR under a model of environmental heterogeneity.
A separate model estimates the travel FoI or AR.
The total FoI is the sum of expected time spent traveling.