The models in this chapter use Subscripts and can only be developed in Vensim Professional and DSS.
In Chapter 5 we introduced a small market growth model showing some advantages to responding less quickly to market demand, with a smoother, but more prolonged, transition to sustained replacement. This result quickly loses its meaning when the prospect of competition is introduced. In this case, being slow to respond may mean losing the business to competitors.
This chapter describes how to create equations that allow us to look at the consequences of having more than one producer in the market growth model. To achieve this, we use the Subscript capabilities of Vensim Professional and DSS. While this chapter may prove interesting reading for users of Vensim Standard, you will not be able to construct or simulate the model as described. Constructing a two sector model (for production), if you wish to pursue it, can be done by replicating the production sector and linking the sectors to the customer view by adding in the appropriately modified coordinating equations (described in this chapter for the subscripted model).
