Question

the simple SIR model of Kermack and McKendrik (4). In this model, a population is divided into susceptible, infective and recovered individuals, with the functions S(t), I(t) and R(t) denoting their respective fractions in the populations at time t (measured, for example, in days). The evolution of these quantities is described by the differential equations: ds dt -BSI dt dR dt = BSI - I EI (a) Is it linear or nonlinear? If it is linear, is it a linearization of a nonlinear model? If it is nonlinear, what is the linearized version? What is assumed when the model is linear? Or what is NOT assumed when the model is linear? Does the nonlinearity improve the linear model? Give an explanation to your answer. (b) Calculate the equilibrium points. What do they represent?

Answer 1

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