Communicating population forecast uncertainty using perishable food terminology

Despite many decades of research on probabilistic methods, population forecasts with predictive distributions remain relatively rare amongst official population forecasts. Partly as a result, little attention has been given to communicating forecast uncertainty to users, especially non-technical users. The aim of this paper is to propose the adoption of perishable food labels such as ‘shelf life’, ‘use by’ date, and ‘best before’ date to describe forecast uncertainty in a simple manner. These terms can be applied to both fully probabilistic forecasts and those with empirical prediction intervals based on past error distributions. Examples of their use are presented using population forecasts for the World, Australia, and the Northern Territory of Australia. It is suggested that these labels could prove helpful in describing uncertainty to non-technical users of population forecasts.