Join Data Frames

The join operation between data frames is among the most important operations on data because it is not just technically powerful; it is one of the pillars of the creativity and exploration intrinsic to data science. This chapter utilizes datasets Gini index, from the World Bank, and Military spending as a share of GDP, from Our World in Data/SIPRI, and assume we want to join their rows by respecting the logical associations between countries listed in the two datasets. Gini index, from the World Bank, presents indicators measuring the distribution of income, wealth, or consumption across the population for a large set of countries. As usual with Python and pandas, indexes could be actively exploited in data wrangling operations.