A
primate city is the largest city in its country or region, disproportionately larger than any others in the
urban hierarchy. A 'primate city distribution' is a
rank-size distribution that has one very large city with many much smaller cities and towns, and no intermediate-sized urban centres: a
King effect, visible as an outlier on an otherwise linear graph, when the rest of the data fit a
power law or
stretched exponential function. The 'law of the primate city' was first proposed by the
geographer Mark Jefferson in 1939. He defines a primate city as being "at least twice as large as the next largest city and more than twice as significant." A primate city is number one in its country in most aspects, like politics, economy, media, culture and universities.