Consider Muths famous chicken or egg model of urban growth. It is written that: dE aM

Consider Muth’s famous ‘‘chicken or egg’’ model of urban growth. It is written that:

dE ¼ aM M ¼ b dð Þþ E u;

where E is employment in the urban area, dE is the change in employment, M is migration into the urban area, and u is an exogenous amount of in-migration.

a. Why might migration increase when the change in employment (dE) increases?

b. Suppose that a ¼ 0.5 and b ¼ 0.4. What is the change in employment (dE) when u changes by 1?

c. For the model to be ‘‘stable,’’ it must be true that ab is less than 1.0. Why? What is meant by stability here?