Wassily Leontief won a Nobel Memorial Prize for Economics in 1974 because of his work to create a matrix-based analytical framework for economic modelling. That work was rooted in early 1920's work in the USSR and developments to the point where Leontief created a computer-based model of the US Economy at the turn of the 1950's.
As just one illustration of the utility of such a model -- despite the limitations of its implied linearisation of an inherently nonlinear system, my late Father used an early 23 sector model of Jamaica's economy in the mid-1960's to project development issues and concerns across 20 years, drawing attention to needed strategic interventions to draw out and initially address an almost Malthusian imbalance between population, investment, education gaps and productive potential of the workforce, unemployment and general social welfare.
The following tutorial in four parts (at YouTube -- not a general endorsement, given the rapid rise of web censorship in recent months . . . ) may be helpful to those needing a basic introduction:
PART 1:
PART 2:
PART 3:
PART 4:
Such models have now been greatly extended and are a basis for modelling as far afield as energy sustainability and the like. END
