I recently prepared a Google Slides presentation on Biproportional MMP, a variant of the Mixed Member Proportional (MMP) voting system. The distinguishing feature of Biproportional MMP is that the top-up seats which make election results proportional are allocated at the territory-wide level, then distributed among smaller regions. Others had thought of this idea before me, but I felt there was a need for a single reference describing the model and defining an electoral formula.

Click here for the Google Slides presentation of Biproportional MMP