How e dey work, well well
For each list, calculate di series votes/1, votes/2, votes/3… Di seats go to di biggest quotients across all lists, until dem finish.
Dis highest-average rule dey favour big lists small, systematically and everybody sabi: na political choice for governability, no be calculation accident.
Threshold (5 % for Germany, 3 % for French European elections) dey remove very small lists before sharing, to avoid scatter-scatter.
Example wey get figures
Hundred votes, five seats to share between three lists with D'Hondt.
| List | Votes | ÷1 | ÷2 | ÷3 |
|---|---|---|---|---|
| A | 45 | 45 | 22.5 | 15 |
| B | 35 | 35 | 17.5 | 11.7 |
| C | 20 | 20 | 10 | 6.7 |
- Di five biggest quotients across all lists: 45 (A), 35 (B), 22.5 (A), 20 (C), 17.5 (B).
- Final sharing: A 2 seats, B 2 seats, C 1 seat.
- A get 40 % of di seats with 45 % of di votes; C get 20 % of di seats with 20 % of di votes.
With small number of seats, proportionality must be rough — na di number of seats, pass di formula, dey decide how fine di representation fit be.
Where e come from
Di Belgian jurist Victor d'Hondt bring out im method since 1878, for one pamphlet wey e publish without im name, and systematise am as book for 1882; Belgium adopt am through di 1899 law and use am from di 1900 elections — first for di whole world. Dem don already sabi di formula: Thomas Jefferson propose am for 1792 to share House seats among di American states.
Rival variants dey since dat time: Sainte-Laguë (1910), same as di Webster method of 1832, dey treat small parties better and e still be di reference for Scandinavia and New Zealand.
Di largest-remainder method, wey dem call Hamilton own, dem drop am for United States after di Alabama paradox: for 1880 dem see say to raise di total seats from 299 to 300 MAKE Alabama lose one seat. United States dey use di Huntington-Hill method since 1941.
Where dem dey use am
- Parliament elections for most European democracies.
- European elections, and French regional elections for di proportional part.
- To compose board of directors or association committee.
- To share budget or slots between groups, according to support.
Limits and wahala
- E reflect opinion well well
- E give minority space
- Small vote dey waste
- No clear single winner
- E fit force coalition
- Di threshold go comot di smallest
Questions wey people dey ask
D'Hondt or Sainte-Laguë?
D'Hondt (divide by 1, 2, 3…) dey favour big lists small and dey make majority easy. Sainte-Laguë (by 1, 3, 5…) dey more faithful to small ones. Di choice na political and you must make am before di vote, never after.
Why my seat percentages no match di votes?
Because you no fit cut seat into two. With five seats, di smallest step na 20 %: no formula fit do better. Di gap dey close as di number of seats dey grow.
I fit use am for small group?
Yes, to share resources — slots, budget, places. To choose between options, use approval or Condorcet instead.
Sources
Di main books and papers wey dis page stand on.
- D'Hondt, Victor (signé « par un électeur »), Question électorale. La représentation proportionnelle des partis, Bruxelles, 1878.
- D'Hondt, Victor, Système pratique et raisonné de représentation proportionnelle, Librairie C. Muquardt, Bruxelles, 1882.
- Balinski, Michel L. et Young, H. Peyton, Fair Representation: Meeting the Ideal of One Man, One Vote, Yale University Press (2e édition, Brookings, 2001), 1982.
- Sainte-Laguë, André, La représentation proportionnelle et la méthode des moindres carrés, Annales scientifiques de l'École normale supérieure, 3e série, 27, 529-542, 1910.
- Gallagher, Michael, Proportionality, Disproportionality and Electoral Systems, Electoral Studies, 10(1), 33-51, 1991. DOI ↗