clipped from: www.sciencenews.org   

A country's competitive edge can spread industry to industry, like a disease

The economies of poor and developing countries often depend almost exclusively on a single product—perhaps timber or coffee—or on a handful of products at most.
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HIDDEN LINKS. In the product space network above, nodes represent products. The more closely products are linked, the more likely they are to be produced and exported by the same countries. Each node's size represents the total world trade in that product, and the nodes' colors follow an older classification of products.
Hidalgo/Science

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REGIONAL DIFFERENCES. In these illustrations, black squares mark products successfully exported. The industrialized countries' products (left) occupy the highly connected core of world trade. Goods from Southeast Asia and the Pacific region (center) cluster in the garment industry and in electronics, while sub-Saharan Africa's products (right) are mostly peripheral.
Hidalgo/Science