A New Heuristic Algorithm for Balanced Deliberation Groups

We here present an improved version of the Sortition Foundation's GROUPSELECT software package, which aims to repeatedly allocate participants of a deliberative process to discussion groups in a way that balances demographics in each group and maximises distinct meetings over time. Our result, GROUPOPT, significantly outperforms the prior algorithmic approach LEGACY. We also add functionalities to the GROUPSELECT software to help the end user. The GROUPOPT algorithm utilises random shuffles and Pareto swaps to find a locally optimal solution that maximises demographic balance and minimises the number of pairwise previous meetings, with the relative importance of these two metrics defined by the user.