United Nations World Population Projections with R
Recently, the United Nations adopted a probabilistic approach to projecting fertility, mortality and population for all countries. In this approach, the total fertility and female and male life expectancy at birth are projected using Bayesian hierarchical models estimated via Markov Chain Monte Carlo. They are then combined yielding probabilistic projections for any population quantity of interest. The methodology is implemented in a suite of R packages which has been used by the UN to produce the most recent revision of the World Population Prospects. I will summarize the main ideas behind each of the packages, namely bayesTFR, bayesLife, bayesPop, bayesDem, and the shiny-based wppExplorer. I will also touch on our experience of the collaboration between academics and the UN.