  When delegations to an assembly or council represent differently sized
constituencies, they are often allocated voting weights which increase in
population numbers (EU Council, US Electoral College, etc.). The Penrose square
root rule (PSRR) is the main benchmark for fair representation of all
bottom-tier voters in the top-tier decision making body, but rests on the
restrictive assumption of independent binary decisions. We consider intervals
of alternatives with single-peaked preferences instead, and presume positive
correlation of local voters. This calls for a replacement of the PSRR by a
linear Shapley rule: representation is fair if the Shapley value of the
delegates is proportional to their constituency sizes.
