2. Model formulation of basic model
The basic model is based on monitoring the dynamics of the sub-populations of potential smokers (nonsmokers); P(t), smokers; S(t), smokers who temporarily quit smoking; Qt(t), and smokers who permanently quit smoking; Qp(t). Thus, the total population at time t is given by N(t) = P(t) + S(t) + Qt(t) + Qp(t).