An emerging economy is one that is moving from developing to developed (or industrial),while a transition economy is one evolving from a planned economy (meaning one controlled by the government, as in the former Soviet bloc countries) to a free market economy like those in North America and Europe. A country may be both emerging and transitional. Countries undergoing these economic shifts experience varying degrees of progress regarding their impoverished citizens. Generally, a great number of people are able to enter the middle class during such a transition because of increased business opportunities. At the same time, the incidence of poverty and extreme poverty can increase as the very poor have little or no access to such opportunities.
Researchers of poverty use a measurement called the Gini coefficient to discuss income equality—that is, the poverty gap. Developed by the Italian statistician Corrado Gini in 1912, the Gini coefficient is a number between zero and one, with zero representing perfect equality and one representing perfect inequality. Scholars often use the Gini coefficient to express how wide the gap is between the very poor and those with higher incomes.