Using a measure of economic complexity described in this paper, Hidalgo locates the economies of the world in a quantified representation of that basic conceptual space. Two points are worth of note. First, the countries locate themselves along a diagonal with almost every world economy being located in either the first or the fourth quadrant. As summarized by Ethan Zuckerman:
The nations that make only a few things all tend to make, more or less, the same things. Basically, we can divide the world into two sets of countries – those that have sufficient personbytes of knowledge to produce a wide range of goods, and those that can produce only a few simple things. The places that make everything make things that few others make. Hausmann explains that products require a specific set of personbytes to produce. When you gain additional personbytes of skill, it’s like getting new letters in Scrabble – you can produce a new set of words, but only within the constraints of the letters (skills, knowledge) you already have.Second, this approach does a much better job than traditional economic analysis in addressing the classic question: "Why are some countries rich and other countries poor?" It explains 73% of the variance in income across nations.
Hidalgo describes his approach to complexity economics in the following two videos.
The same basic ideas are covered in more detail in this version.
His webpage is a wealth of information, including (among other things) pages with links to all his publications, to supporting materials for classes on complex systems, and access to the data sets used in his research.