This example shows bubbles with area proportional to each country’s population (2016) superimposed on a world map. Bubbles are also colored according to the continent.
Showing population and geography together, this map could probably be better redesigned as a choropleth of population density. This example is an exercise to prepare for different kinds of data, for which a geographical density would not make sense.
Population data is obtained from data.worldbank.org. The name of the source is “World Development Indicators” and was last updated on 2017, August 2nd.
Based on this example about implementing a map of the world and this one about population bubbles.