Mathematical and Minischeme Appendix

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Constant Definitions

In addition to the helper functions, "Smallpox Attack" identifies a set of constants, parameters of the model. In our simulator, we define them as global minischeme variables. Please refer to the article for a detailed explanation of the meaning of each of these constants.
Description of Variable Minischeme Variable Definition
Infection rate (val beta 0.0000001)
Names generated by index (val c 50)
Fraction of infectees named by index (val p 0.5)
Population size (val N 10000000)
Disease stage 1 rate (val r1 (/ 1 3))
Disease stage 2 rate (val r2 (/ 1 8))
Disease stage 3 rate (val r3 (/ 1 3))
Disease stage 4 rate (val r4 (/ 1 12))
Number of vaccinators (val nv 5000)
Fraction febrile in stage 3 (val h 0.9)
Quarantine rate (val alpha (/ 1 5))
Vaccine efficacy, stage 0 (val nu0 0.975)
Vaccine efficacy, stage 1 (val nu1 0.975)
Smallpox death rate (val delta 0.3)
Vaccination fatality rate (val f 0.000001)
Response time (val tau 5)
Service rate (val mu 0)
(if mass-vaccination
    (set mu 200)
    (set mu 50))
Size of time-unit in days (val time-step [your value here])

Variable mass-vaccination is set to 1 (meaning true) if we want to model a mass vaccination scenario, and to 0 (false) if we want to model a trace vaccination scenario. Variable time-step is measured in days per time-unit, and equals the fraction of a day over which the time model will linearize the functions. A discussion of what this means follows.

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