Economic base ideas can be easy to understand, as are measures made of employment. For instance, it is well known that the economy of
Seattle, Washington is tied to aircraft manufacturing, that of
Detroit, Michigan, to automobiles, and that of
Silicon Valley to high-tech manufacturing. When newspapers discuss the closing of military bases, they may say something like: "5,000 jobs at the base will be lost. That's going to hit the economy hard because it means a loss of 10,000 jobs in the community." To forecast, the main procedure is to compare the region with the nation and national trends. If the economic base of a region is in industries that are declining nationwide, then the region faces a problem. If its economic base is concentrated in sectors that are growing, then it is in good shape. Methodologically, economic base analysis views the region as if it were a small nation and uses notions of relative and comparative advantage from international trade theory (
Charles Tiebout 1963). In a sense, the activity is macroeconomics "written small", and it has not been of much interest to urban economists in recent years because it does not get at within-city relationships. The analysis usually takes US growth patterns as a given. The fates of regions are determined by trends in the national economy. ==Assumptions==