The two halves of proportional representation in electoral systems.

[Donald Ian Rankin]

The constituency-based electoral systems used in the UK, US etc have two main effects.

1) They mean that the result of the election depends not just on how many votes are cast for each option, but *where* those votes are cast. People who live in borderline seats wield far more power than people in safe seats.

2) They convert pluralities into majorities. My understanding is that in the UK, in general parties with votes in proportion p:q will receive MPs in proportions roughly p^3:q^3.

I regard the first of these as a bug, and the second as a feature. If I were setting up an electoral system, I would go for something like "disproportional representation" - power assigned according to some superlinear function of the number of votes received, without reference to their distribution.