Previously perceived as a "soft" skill, " Hobsbawm, who also runs networking business Editorial Intelligence, says effective networking will make the difference "between a highly skilled worker and an average worker.

CNN: Professor of networking on the power of schmoozing

In a 2009 paper Mr Glaeser and Matthew Resseger of Harvard University find that in highly skilled areas, city size explains 45% of the variation in worker productivity (it has almost no effect in underskilled cities).

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