If age and mid_point are positive numbers, if pop_prev
is a positive number between 0 and 1 and if slope is a valid number,
then convert_age_to_cir returns a number, which is equal to
the cumulative incidence rate.
Arguments
age
A non-negative number representing the individual's age.
pop_prev
A positive number representing the overall
population prevalence. Must be at most 1. Defaults to 0.1.
mid_point
A positive number representing the mid point
logistic function. Defaults to 60.
slope
A number holding the rate of increase.
Defaults to 1/8.
Details
Given a person's age, convert_age_to_cir can be used
to compute the cumulative incidence rate (cir), which is given
by the formula
$$pop\_ prev / (1 + exp((mid\_ point - age) * slope))$$