Parliamentary Seat Allocation by the Sainte-Laguë Method

example

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seats

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This Demonstration illustrates Sainte-Laguë's method of allocating parliamentary seats.

The party with the most electoral votes obtains the first seat. Each subsequent seat is then awarded to the party

p

for which the quantity

q(p)=v(p)/(2s(p)+1)

is the largest. Here

v(p)

denotes the number of votes party

p

has received in the election, while

s(p)

is the number of parliamentary seats already allocated to party

p

.

In the pie chart, the inner ring shows the actual electoral votes, while the outer ring displays the number of seats awarded.