Knowledge (XXG)

Sequential proportional approval voting

Source 📝

913: 955: 48: 888: 900: 1102: 1110:
Each voter casts their vote by selecting the candidates they support. The following table shows the results of the votes. Each row starts by saying how many voters voted in that way and marks each candidate that group of voters supported. The bottom row shows the number of votes each candidate received.
1013:
Each ballot is assigned a value equal to the reciprocal of one more than the number of candidates approved on that ballot who have been designated as elected. Each ballot is counted at its current value as a vote for all continuing candidates approved on that ballot. The candidate with the most votes
1109:
For this example, there is an election for a committee with 3 winners. There are six candidates from two main parties: A, B, and C from one party, and X, Y, and Z from another party. About 2/3 of the voters support the first party, and the other roughly 1/3 of the voters support the second party.
1498:, because not as many of the votes for Candidate X were halved. In round 3, anyone who voted for either Candidates C or X has their vote count 1/2, and anyone who voted for both has their vote count 1/3. If anyone had voted for neither, their vote would remain at 1. Below is that table. 1293:, and their vote is not counted in later rounds. For the second round, anyone who voted for Candidate C has their vote counted as only 1/2. Below is the chart for round 2. A second column on the left has been added to indicate the weight of each ballot. 1009:
Sequential Proportional Approval Voting (SPAV) uses Approval Voting ballots to elect multiple winners equitably by selecting a candidate in each round and then reweighing the approvals for the subsequent rounds.
1954: 1050: 941: 2291: 2131: 1056:
is the number of candidates approved on that ballot who were already elected, until the required number of candidates is elected. This reweighting is based on the
2096:
Aziz, Haris; Serge Gaspers, Joachim Gudmundsson, Simon Mackenzie, Nicholas Mattei, Toby Walsh (2014). "Computational Aspects of Multi-Winner Approval Voting".
2901: 2741: 1086:, permitting votes to be counted either by hand or by computer, rather than requiring a computer to determine the outcome of all but the simplest elections. 2509: 632: 1706:
had been used instead, the final committee would be all three candidates from the first party, as they had the highest three vote totals without scaling.
1105:
Illustration of the example election. Candidates with the most votes wins for each round. When a candidate is elected they are removed for the next round.
2080: 1093:, SPAV is better at selecting more central candidates, that represent all the voters, where STV is better at mimicking the distribution of the voters. 1001:
from 1909-1921, when it was replaced by a cruder "party-list" style system as it was easier to calculate, and is still used for some local elections.
1702:. The final result has 2/3 winners from the party that had about 2/3 of the votes, and 1/3 winner from the party that had about 1/3 of the votes. If 2637: 2489: 664: 526: 521: 2736: 934: 627: 2499: 2284: 2185:
Sánchez-Fernández, Luis; Elkind, Edith; Lackner, Martin; Fernández, Norberto; Fisteus, Jesús; Val, Pablo Basanta; Skowron, Piotr (2017-02-10).
309: 2158: 2115: 2062: 833: 2863: 1952: 84: 2906: 2546: 927: 2277: 2254:
Aziz, H., Brill, M., Conitzer, V., et al. (2014): "Justified Representation in Approval-Based Committee Voting", arXiv:1407.8269 p5
2234: 1014:
in the round is elected. The process continues until the number of elected candidates is equal to the number of seats to be filled.
2881: 1017:
At each stage, the unelected candidate with the highest approval score is elected. Then the value of each voter’s ballot is set at
828: 2731: 2677: 818: 568: 539: 479: 2529: 2858: 550: 75: 2657: 613: 2164: 255: 240: 225: 2700: 2685: 2504: 1874: 1869: 1803: 1083: 1076: 986: 871: 491: 414: 335: 2751: 2474: 2464: 2325: 303: 285: 126: 1951:
E. Phragmén (1899): "Till frågan om en proportionell valmetod." Statsvetenskaplig tidskrifts Vol. 2, No. 2: pp 87-95
856: 2716: 2407: 2028: 747: 730: 697: 677: 461: 449: 419: 220: 178: 111: 555: 2766: 2721: 2667: 2579: 603: 596: 80: 2911: 2756: 2642: 2600: 2519: 2444: 2380: 2338: 1889: 1715: 1090: 657: 585: 574: 437: 424: 407: 384: 362: 325: 315: 2375: 990: 2257: 2153:. AAMAS '19. Richland, SC: International Foundation for Autonomous Agents and Multiagent Systems: 1946–1948. 2781: 2771: 2746: 2562: 2439: 2078: 1879: 783: 637: 320: 2822: 2761: 2624: 2567: 1743: 812: 692: 622: 429: 2726: 2647: 2412: 720: 560: 444: 250: 229: 161: 139: 912: 778: 1718:
whenever the committee size is at most 5, but might violate it when the committee size is at least 6.
1491:
Despite Candidates A and B having so many votes in the first round, Candidate X is the second winner,
1071:
where a voter may withhold approval from candidates who are likely to be elected in any case, as with
1020: 2796: 2365: 851: 838: 806: 70: 2776: 2370: 1061: 757: 591: 244: 954: 2817: 2427: 2226: 2198: 2125: 2101: 2003: 1995: 1934: 994: 917: 788: 399: 183: 2385: 866: 2786: 2695: 2652: 2572: 2494: 2417: 2402: 2360: 2218: 2154: 2111: 2058: 2050: 1987: 1926: 1730: 1072: 1057: 823: 793: 715: 652: 486: 213: 188: 171: 39: 2827: 2459: 2315: 2300: 2208: 2151:
Proceedings of the 18th International Conference on Autonomous Agents and MultiAgent Systems
2098:
Proceedings of the 2015 International Conference on Autonomous Agents and Multiagent Systems
1979: 1918: 978: 904: 861: 752: 740: 454: 330: 156: 150: 132: 121: 116: 104: 65: 27: 2875: 2791: 2632: 2610: 2422: 2343: 2333: 2311: 2261: 2084: 1958: 1884: 1772: 1703: 1068: 982: 892: 725: 580: 545: 466: 377: 280: 203: 145: 23: 2186: 47: 2690: 2395: 2355: 762: 702: 687: 498: 367: 342: 193: 887: 2895: 2434: 2007: 1911:"The Excess Method: A Multiwinner Approval Voting Procedure to Allocate Wasted Votes" 771: 471: 259: 97: 60: 35: 2230: 1938: 2449: 2390: 2145:
Faliszewski, Piotr; Skowron, Piotr; Szufa, Stanisław; Talmon, Nimrod (2019-05-08).
511: 275: 268: 198: 2146: 2832: 2595: 2534: 2454: 2350: 1101: 389: 347: 290: 235: 2605: 2541: 2222: 2213: 1991: 1930: 2842: 2837: 2077:
Steven J. Brams, D. Marc Kilgour (2009): "Satisfaction Approval Voting": p4
357: 352: 1910: 899: 2662: 1922: 608: 2022: 2524: 1999: 394: 997:
in the early 1900s. It was used (with adaptations for party lists) in
2812: 1286:
Because Candidate C has the most support, they are the first winner,
998: 2269: 2106: 1983: 2203: 2255: 1100: 953: 1970:
Lewis, Edward G. (1950). "Review of Modern Foreign Governments".
2273: 2191:
Proceedings of the AAAI Conference on Artificial Intelligence
1082:
It is a much computationally simpler algorithm than harmonic
985:
to a multiple winner election. It is a simplified version of
46: 2024:
Proportional Representation: A Study in Methods of Election
1089:
When comparing Sequential Proportional Approval Voting to
2147:"Proportional Representation in Elections: STV vs PAV" 1714:
Sequential-PAV satisfies the fairness property called
1060:(Jefferson method). Other weighting formulas such as 1023: 2053:. In Jean-François Laslier; M. Remzi Sanver (eds.). 2851: 2805: 2709: 2676: 2623: 2588: 2555: 2482: 2473: 2324: 1064:may be used while still being referred to as SPAV. 1044: 2051:"Approval Balloting for Multi-winner Elections" 1751:Support monotonicity without additional voters 2285: 935: 8: 2742:Independence of Smith-dominated alternatives 2130:: CS1 maint: multiple names: authors list ( 1695:Candidate B is the third and final winner, 2479: 2292: 2278: 2270: 942: 928: 18: 2212: 2202: 2105: 1024: 1022: 1723: 1500: 1295: 1112: 2737:Independence of irrelevant alternatives 2515:Sequential proportional approval voting 2187:"Proportional Justified Representation" 1901: 1835:Sequential Proportional Approval Voting 963:Sequential proportional approval voting 34: 2123: 1972:The American Political Science Review 1909:Brams, Steven; Brill, Markus (2018). 7: 2902:Semi-proportional electoral systems 2547:Indirect single transferable voting 993:, proposed by Danish statistician 14: 2021:Humphreys, John H. (2006-01-01). 1045:{\displaystyle {\frac {1}{s+1}}} 911: 898: 886: 834:McKelvey–Schofield chaos theorem 480:Semi-proportional representation 112:First preference plurality (FPP) 16:Multiple-winner electoral system 2237:from the original on 2021-06-24 2167:from the original on 2022-05-11 2031:from the original on 2022-05-11 2658:Mixed ballot transferable vote 2057:. Springer. pp. 105–124. 1067:There is an incentive towards 958:Flow chart of SPAV calculation 872:Harsanyi's utilitarian theorem 829:Moulin's impossibility theorem 794:Conflicting majorities paradox 1: 698:Frustrated majorities paradox 2859:Comparison of voting systems 2701:Satisfaction approval voting 2686:Single non-transferable vote 2505:Proportional approval voting 1875:Satisfaction approval voting 1870:Proportional approval voting 1804:Proportional approval voting 1761:inclusion- strategyproofness 1084:proportional approval voting 1077:single non-transferable vote 987:proportional approval voting 981:that extends the concept of 867:Condorcet dominance theorems 807:Social and collective choice 2465:Graduated majority judgment 2055:Handbook on Approval Voting 533:By mechanism of combination 304:Proportional representation 2928: 2907:Cardinal electoral systems 2717:Condorcet winner criterion 2408:First-past-the-post voting 989:. It is a special case of 971:reweighted approval voting 731:Multiple districts paradox 462:Fractional approval voting 450:Interactive representation 2872: 2864:Voting systems by country 2767:Mutual majority criterion 2722:Condorcet loser criterion 2668:Vote linkage mixed system 2580:Largest remainders method 2307: 2049:Kilgour, D. Marc (2010). 678:Paradoxes and pathologies 527:Mixed-member proportional 522:Mixed-member majoritarian 517:By results of combination 408:Approval-based committees 2757:Majority loser criterion 2643:Additional member system 2601:Hagenbach-Bischoff quota 2520:Single transferable vote 2445:Positional voting system 2381:Minimax Condorcet method 2339:Combined approval voting 2214:10.1609/aaai.v31i1.10611 1890:Single transferable vote 1766:Computational complexity 1716:justified representation 1091:Single Transferable Vote 857:Condorcet's jury theorem 658:Double simultaneous vote 633:Rural–urban proportional 628:Dual-member proportional 590: 579: 546:Parallel (superposition) 438:Fractional social choice 425:Expanding approvals rule 254: 239: 224: 155: 144: 120: 2782:Resolvability criterion 2772:Participation criterion 2747:Later-no-harm criterion 2563:Highest averages method 1915:SSRN Electronic Journal 1880:Reweighted range voting 784:Tyranny of the majority 561:Fusion (majority bonus) 378:Quota-remainder methods 2823:First-preference votes 2762:Monotonicity criterion 2732:Independence of clones 2435:Simple majoritarianism 1746:with additional voters 1737:Committee monotonicity 1114:Votes from 200 voters 1106: 1046: 959: 918:Mathematics portal 824:Majority impossibility 813:Impossibility theorems 609:Negative vote transfer 430:Method of equal shares 51: 2727:Consistency criterion 2648:Alternative vote plus 2413:Instant-runoff voting 1297:Second Round Results 1104: 1047: 991:Thiele's voting rules 957: 721:Best-is-worst paradox 710:Pathological response 445:Direct representation 98:Single-winner methods 50: 2797:Seats-to-votes ratio 2568:Webster/Sainte-Laguë 2100:. pp. 107–115. 1923:10.2139/ssrn.3274796 1502:Third Round Results 1021: 905:Economics portal 852:Median voter theorem 71:Comparative politics 2777:Plurality criterion 2376:Kemeny–Young method 1503: 1298: 1115: 1062:Sainte-Lague method 893:Politics portal 604:Vote linkage system 575:Seat linkage system 162:Ranked-choice (RCV) 2818:Election threshold 2752:Majority criterion 2428:Supplementary vote 2260:2017-04-13 at the 2083:2012-06-28 at the 1957:2015-06-18 at the 1501: 1296: 1113: 1107: 1042: 995:Thorvald N. Thiele 960: 789:Discursive dilemma 748:Lesser evil voting 623:Supermixed systems 326:Largest remainders 184:Round-robin voting 52: 2889: 2888: 2787:Reversal symmetry 2696:Cumulative voting 2678:Semi-proportional 2653:Mixed single vote 2619: 2618: 2495:Mixed single vote 2403:Exhaustive ballot 2366:Copeland's method 2361:Condorcet methods 2301:Electoral systems 2160:978-1-4503-6309-9 2117:978-1-4503-3413-6 2064:978-3-642-02839-7 1861: 1860: 1731:Pareto efficiency 1693: 1692: 1489: 1488: 1284: 1283: 1073:cumulative voting 1040: 952: 951: 839:Gibbard's theorem 779:Dominance paradox 716:Perverse response 420:Phragmen's method 286:Majority judgment 214:Positional voting 172:Condorcet methods 40:electoral systems 2919: 2828:Liquid democracy 2480: 2460:Two-round system 2371:Dodgson's method 2294: 2287: 2280: 2271: 2264: 2252: 2246: 2245: 2243: 2242: 2216: 2206: 2182: 2176: 2175: 2173: 2172: 2142: 2136: 2135: 2129: 2121: 2109: 2093: 2087: 2075: 2069: 2068: 2046: 2040: 2039: 2037: 2036: 2018: 2012: 2011: 1967: 1961: 1949: 1943: 1942: 1906: 1724: 1504: 1299: 1116: 1051: 1049: 1048: 1043: 1041: 1039: 1025: 979:electoral system 944: 937: 930: 916: 915: 903: 902: 891: 890: 846:Positive results 741:Strategic voting 638:Majority jackpot 595: 584: 455:Liquid democracy 331:National remnant 321:Highest averages 258: 243: 228: 160: 151:Alternative vote 149: 133:Partisan primary 125: 66:Mechanism design 19: 2927: 2926: 2922: 2921: 2920: 2918: 2917: 2916: 2912:Approval voting 2892: 2891: 2890: 2885: 2868: 2847: 2801: 2792:Smith criterion 2705: 2672: 2633:Parallel voting 2615: 2611:Imperiali quota 2584: 2551: 2469: 2423:Contingent vote 2386:Nanson's method 2344:Unified primary 2334:Approval voting 2320: 2303: 2298: 2268: 2267: 2262:Wayback Machine 2253: 2249: 2240: 2238: 2184: 2183: 2179: 2170: 2168: 2161: 2144: 2143: 2139: 2122: 2118: 2095: 2094: 2090: 2085:Wayback Machine 2076: 2072: 2065: 2048: 2047: 2043: 2034: 2032: 2020: 2019: 2015: 1984:10.2307/1950372 1969: 1968: 1964: 1959:Wayback Machine 1950: 1946: 1908: 1907: 1903: 1898: 1885:Approval voting 1866: 1773:Approval voting 1721: 1712: 1704:approval voting 1700: 1496: 1291: 1099: 1069:tactical voting 1029: 1019: 1018: 1007: 983:approval voting 948: 910: 909: 897: 885: 877: 876: 843: 819:Arrow's theorem 809: 799: 798: 767: 737: 726:No-show paradox 707: 693:Cloning paradox 683:Spoiler effects 680: 670: 669: 644: 531: 514: 504: 503: 476: 467:Maximal lottery 434: 415:Thiele's method 404: 374: 306: 296: 295: 281:Approval voting 269:Cardinal voting 265: 210: 204:Maximal lottery 168: 100: 90: 17: 12: 11: 5: 2925: 2923: 2915: 2914: 2909: 2904: 2894: 2893: 2887: 2886: 2873: 2870: 2869: 2867: 2866: 2861: 2855: 2853: 2849: 2848: 2846: 2845: 2840: 2835: 2830: 2825: 2820: 2815: 2809: 2807: 2803: 2802: 2800: 2799: 2794: 2789: 2784: 2779: 2774: 2769: 2764: 2759: 2754: 2749: 2744: 2739: 2734: 2729: 2724: 2719: 2713: 2711: 2707: 2706: 2704: 2703: 2698: 2693: 2691:Limited voting 2688: 2682: 2680: 2674: 2673: 2671: 2670: 2665: 2660: 2655: 2650: 2645: 2640: 2635: 2629: 2627: 2621: 2620: 2617: 2616: 2614: 2613: 2608: 2603: 2598: 2592: 2590: 2586: 2585: 2583: 2582: 2577: 2576: 2575: 2570: 2559: 2557: 2553: 2552: 2550: 2549: 2544: 2539: 2538: 2537: 2532: 2527: 2517: 2512: 2507: 2502: 2497: 2492: 2486: 2484: 2477: 2471: 2470: 2468: 2467: 2462: 2457: 2452: 2447: 2442: 2437: 2432: 2431: 2430: 2425: 2420: 2418:Coombs' method 2410: 2405: 2400: 2399: 2398: 2396:Schulze method 2393: 2388: 2383: 2378: 2373: 2368: 2358: 2356:Bucklin voting 2353: 2348: 2347: 2346: 2341: 2330: 2328: 2322: 2321: 2308: 2305: 2304: 2299: 2297: 2296: 2289: 2282: 2274: 2266: 2265: 2247: 2177: 2159: 2137: 2116: 2088: 2070: 2063: 2041: 2013: 1978:(1): 209–211. 1962: 1944: 1900: 1899: 1897: 1894: 1893: 1892: 1887: 1882: 1877: 1872: 1865: 1862: 1859: 1858: 1855: 1852: 1849: 1846: 1843: 1840: 1837: 1831: 1830: 1827: 1824: 1821: 1818: 1815: 1812: 1807: 1799: 1798: 1795: 1792: 1789: 1786: 1783: 1780: 1775: 1769: 1768: 1763: 1758: 1753: 1748: 1739: 1734: 1727: 1711: 1708: 1698: 1691: 1690: 1687: 1684: 1682: 1680: 1677: 1674: 1672: 1671:Weighted Votes 1668: 1667: 1665: 1662: 1659: 1657: 1655: 1653: 1650: 1646: 1645: 1642: 1639: 1636: 1633: 1631: 1629: 1626: 1622: 1621: 1618: 1615: 1612: 1610: 1608: 1606: 1603: 1599: 1598: 1596: 1594: 1591: 1588: 1585: 1582: 1579: 1575: 1574: 1572: 1570: 1568: 1565: 1562: 1560: 1557: 1553: 1552: 1550: 1548: 1546: 1543: 1540: 1537: 1534: 1530: 1529: 1526: 1523: 1520: 1517: 1514: 1511: 1510:Weight of Vote 1508: 1494: 1487: 1486: 1483: 1480: 1477: 1475: 1472: 1469: 1467: 1466:Weighted Votes 1463: 1462: 1460: 1457: 1454: 1452: 1450: 1448: 1445: 1441: 1440: 1437: 1434: 1431: 1428: 1426: 1424: 1421: 1417: 1416: 1413: 1410: 1407: 1405: 1403: 1401: 1398: 1394: 1393: 1391: 1389: 1386: 1383: 1380: 1377: 1374: 1370: 1369: 1367: 1365: 1363: 1360: 1357: 1355: 1352: 1348: 1347: 1345: 1343: 1341: 1338: 1335: 1332: 1329: 1325: 1324: 1321: 1318: 1315: 1312: 1309: 1306: 1305:Weight of Vote 1303: 1289: 1282: 1281: 1278: 1275: 1272: 1269: 1266: 1263: 1259: 1258: 1256: 1253: 1250: 1248: 1246: 1244: 1240: 1239: 1236: 1233: 1230: 1227: 1225: 1223: 1219: 1218: 1215: 1212: 1209: 1207: 1205: 1203: 1199: 1198: 1196: 1194: 1191: 1188: 1185: 1182: 1178: 1177: 1175: 1173: 1171: 1168: 1165: 1163: 1159: 1158: 1156: 1154: 1152: 1149: 1146: 1143: 1139: 1138: 1135: 1132: 1129: 1126: 1123: 1120: 1098: 1095: 1058:D'Hondt method 1038: 1035: 1032: 1028: 1006: 1003: 950: 949: 947: 946: 939: 932: 924: 921: 920: 908: 907: 895: 882: 879: 878: 875: 874: 869: 864: 859: 854: 842: 841: 836: 831: 826: 821: 810: 805: 804: 801: 800: 797: 796: 791: 786: 781: 766: 765: 763:Turkey-raising 760: 755: 750: 736: 735: 734: 733: 723: 718: 706: 705: 703:Center squeeze 700: 695: 690: 688:Spoiler effect 681: 676: 675: 672: 671: 668: 667: 662: 661: 660: 647:By ballot type 643: 642: 641: 640: 635: 630: 620: 619: 618: 617: 616: 611: 601: 600: 599: 588: 565: 564: 563: 558: 553: 548: 530: 529: 524: 515: 510: 509: 506: 505: 502: 501: 499:Limited voting 496: 495: 494: 475: 474: 469: 464: 459: 458: 457: 452: 433: 432: 427: 422: 417: 403: 402: 397: 392: 387: 373: 372: 371: 370: 368:Localized list 365: 360: 355: 350: 340: 339: 338: 336:Biproportional 333: 328: 323: 307: 302: 301: 298: 297: 294: 293: 288: 283: 278: 264: 263: 248: 233: 209: 208: 207: 206: 201: 196: 191: 181: 167: 166: 165: 164: 153: 140:Instant-runoff 137: 136: 135: 127:Jungle primary 114: 103:Single vote - 101: 96: 95: 92: 91: 89: 88: 78: 73: 68: 63: 57: 54: 53: 43: 42: 32: 31: 15: 13: 10: 9: 6: 4: 3: 2: 2924: 2913: 2910: 2908: 2905: 2903: 2900: 2899: 2897: 2884: 2883: 2878: 2877: 2871: 2865: 2862: 2860: 2857: 2856: 2854: 2850: 2844: 2841: 2839: 2836: 2834: 2831: 2829: 2826: 2824: 2821: 2819: 2816: 2814: 2811: 2810: 2808: 2804: 2798: 2795: 2793: 2790: 2788: 2785: 2783: 2780: 2778: 2775: 2773: 2770: 2768: 2765: 2763: 2760: 2758: 2755: 2753: 2750: 2748: 2745: 2743: 2740: 2738: 2735: 2733: 2730: 2728: 2725: 2723: 2720: 2718: 2715: 2714: 2712: 2708: 2702: 2699: 2697: 2694: 2692: 2689: 2687: 2684: 2683: 2681: 2679: 2675: 2669: 2666: 2664: 2661: 2659: 2656: 2654: 2651: 2649: 2646: 2644: 2641: 2639: 2636: 2634: 2631: 2630: 2628: 2626: 2622: 2612: 2609: 2607: 2604: 2602: 2599: 2597: 2594: 2593: 2591: 2587: 2581: 2578: 2574: 2571: 2569: 2566: 2565: 2564: 2561: 2560: 2558: 2554: 2548: 2545: 2543: 2540: 2536: 2533: 2531: 2528: 2526: 2523: 2522: 2521: 2518: 2516: 2513: 2511: 2508: 2506: 2503: 2501: 2498: 2496: 2493: 2491: 2488: 2487: 2485: 2481: 2478: 2476: 2472: 2466: 2463: 2461: 2458: 2456: 2453: 2451: 2448: 2446: 2443: 2441: 2438: 2436: 2433: 2429: 2426: 2424: 2421: 2419: 2416: 2415: 2414: 2411: 2409: 2406: 2404: 2401: 2397: 2394: 2392: 2389: 2387: 2384: 2382: 2379: 2377: 2374: 2372: 2369: 2367: 2364: 2363: 2362: 2359: 2357: 2354: 2352: 2349: 2345: 2342: 2340: 2337: 2336: 2335: 2332: 2331: 2329: 2327: 2326:Single-winner 2323: 2319: 2317: 2313: 2306: 2302: 2295: 2290: 2288: 2283: 2281: 2276: 2275: 2272: 2263: 2259: 2256: 2251: 2248: 2236: 2232: 2228: 2224: 2220: 2215: 2210: 2205: 2200: 2196: 2192: 2188: 2181: 2178: 2166: 2162: 2156: 2152: 2148: 2141: 2138: 2133: 2127: 2119: 2113: 2108: 2103: 2099: 2092: 2089: 2086: 2082: 2079: 2074: 2071: 2066: 2060: 2056: 2052: 2045: 2042: 2030: 2026: 2025: 2017: 2014: 2009: 2005: 2001: 1997: 1993: 1989: 1985: 1981: 1977: 1973: 1966: 1963: 1960: 1956: 1953: 1948: 1945: 1940: 1936: 1932: 1928: 1924: 1920: 1916: 1912: 1905: 1902: 1895: 1891: 1888: 1886: 1883: 1881: 1878: 1876: 1873: 1871: 1868: 1867: 1863: 1856: 1853: 1850: 1847: 1844: 1841: 1838: 1836: 1833: 1832: 1828: 1825: 1822: 1819: 1816: 1813: 1811: 1808: 1806: 1805: 1801: 1800: 1796: 1793: 1790: 1787: 1784: 1781: 1779: 1776: 1774: 1771: 1770: 1767: 1764: 1762: 1759: 1757: 1754: 1752: 1749: 1747: 1745: 1740: 1738: 1735: 1733: 1732: 1728: 1726: 1725: 1722: 1719: 1717: 1709: 1707: 1705: 1701: 1688: 1685: 1683: 1681: 1678: 1675: 1673: 1670: 1669: 1666: 1663: 1660: 1658: 1656: 1654: 1651: 1648: 1647: 1643: 1640: 1637: 1634: 1632: 1630: 1627: 1624: 1623: 1619: 1616: 1613: 1611: 1609: 1607: 1604: 1601: 1600: 1597: 1595: 1592: 1589: 1586: 1583: 1580: 1577: 1576: 1573: 1571: 1569: 1566: 1563: 1561: 1558: 1555: 1554: 1551: 1549: 1547: 1544: 1541: 1538: 1535: 1532: 1531: 1527: 1524: 1521: 1518: 1515: 1512: 1509: 1506: 1505: 1499: 1497: 1484: 1481: 1478: 1476: 1473: 1470: 1468: 1465: 1464: 1461: 1458: 1455: 1453: 1451: 1449: 1446: 1443: 1442: 1438: 1435: 1432: 1429: 1427: 1425: 1422: 1419: 1418: 1414: 1411: 1408: 1406: 1404: 1402: 1399: 1396: 1395: 1392: 1390: 1387: 1384: 1381: 1378: 1375: 1372: 1371: 1368: 1366: 1364: 1361: 1358: 1356: 1353: 1350: 1349: 1346: 1344: 1342: 1339: 1336: 1333: 1330: 1327: 1326: 1322: 1319: 1316: 1313: 1310: 1307: 1304: 1301: 1300: 1294: 1292: 1279: 1276: 1273: 1270: 1267: 1264: 1261: 1260: 1257: 1254: 1251: 1249: 1247: 1245: 1242: 1241: 1237: 1234: 1231: 1228: 1226: 1224: 1221: 1220: 1216: 1213: 1210: 1208: 1206: 1204: 1201: 1200: 1197: 1195: 1192: 1189: 1186: 1183: 1180: 1179: 1176: 1174: 1172: 1169: 1166: 1164: 1161: 1160: 1157: 1155: 1153: 1150: 1147: 1144: 1141: 1140: 1136: 1133: 1130: 1127: 1124: 1121: 1118: 1117: 1111: 1103: 1096: 1094: 1092: 1087: 1085: 1080: 1078: 1074: 1070: 1065: 1063: 1059: 1055: 1036: 1033: 1030: 1026: 1015: 1011: 1004: 1002: 1000: 996: 992: 988: 984: 980: 976: 972: 968: 964: 956: 945: 940: 938: 933: 931: 926: 925: 923: 922: 919: 914: 906: 901: 896: 894: 889: 884: 883: 881: 880: 873: 870: 868: 865: 863: 862:May's theorem 860: 858: 855: 853: 850: 849: 848: 847: 840: 837: 835: 832: 830: 827: 825: 822: 820: 817: 816: 815: 814: 808: 803: 802: 795: 792: 790: 787: 785: 782: 780: 777: 776: 775: 774: 773: 772:majority rule 770:Paradoxes of 764: 761: 759: 756: 754: 751: 749: 746: 745: 744: 743: 742: 732: 729: 728: 727: 724: 722: 719: 717: 714: 713: 712: 711: 704: 701: 699: 696: 694: 691: 689: 686: 685: 684: 679: 674: 673: 666: 663: 659: 656: 655: 654: 651: 650: 649: 648: 639: 636: 634: 631: 629: 626: 625: 624: 621: 615: 612: 610: 607: 606: 605: 602: 598: 593: 589: 587: 582: 578: 577: 576: 573: 572: 571: 570: 566: 562: 559: 557: 554: 552: 549: 547: 544: 543: 542: 541: 536: 535: 534: 528: 525: 523: 520: 519: 518: 513: 512:Mixed systems 508: 507: 500: 497: 493: 490: 489: 488: 485: 484: 483: 482: 481: 473: 472:Random ballot 470: 468: 465: 463: 460: 456: 453: 451: 448: 447: 446: 443: 442: 441: 440: 439: 431: 428: 426: 423: 421: 418: 416: 413: 412: 411: 410: 409: 401: 398: 396: 393: 391: 388: 386: 383: 382: 381: 380: 379: 369: 366: 364: 361: 359: 356: 354: 351: 349: 346: 345: 344: 341: 337: 334: 332: 329: 327: 324: 322: 319: 318: 317: 316:Apportionment 314: 313: 312: 311: 305: 300: 299: 292: 289: 287: 284: 282: 279: 277: 274: 273: 272: 271: 270: 261: 257: 252: 251:Antiplurality 249: 246: 242: 237: 234: 231: 227: 222: 219: 218: 217: 216: 215: 205: 202: 200: 197: 195: 192: 190: 187: 186: 185: 182: 180: 179:Condorcet-IRV 177: 176: 175: 174: 173: 163: 158: 154: 152: 147: 143: 142: 141: 138: 134: 131: 130: 128: 123: 118: 115: 113: 110: 109: 108: 106: 99: 94: 93: 86: 82: 79: 77: 74: 72: 69: 67: 64: 62: 61:Social choice 59: 58: 56: 55: 49: 45: 44: 41: 37: 36:Social choice 33: 29: 25: 21: 20: 2880: 2874: 2514: 2490:Mixed-member 2475:Proportional 2450:Score voting 2391:Ranked pairs 2310:Part of the 2309: 2250: 2239:. Retrieved 2194: 2190: 2180: 2169:. Retrieved 2150: 2140: 2097: 2091: 2073: 2054: 2044: 2033:. Retrieved 2023: 2016: 1975: 1971: 1965: 1947: 1914: 1904: 1834: 1809: 1802: 1777: 1765: 1760: 1755: 1750: 1744:monotonicity 1741: 1736: 1729: 1720: 1713: 1696: 1694: 1528:Candidate Z 1492: 1490: 1323:Candidate Z 1287: 1285: 1137:Candidate Z 1108: 1088: 1081: 1066: 1053: 1016: 1012: 1008: 974: 970: 966: 962: 961: 845: 844: 811: 769: 768: 753:Exaggeration 739: 738: 709: 708: 682: 646: 645: 614:Mixed ballot 569:Compensatory 567: 540:compensatory 537: 532: 516: 478: 477: 436: 435: 406: 405: 376: 375: 363:List-free PR 308: 276:Score voting 267: 266: 212: 211: 199:Ranked pairs 170: 169: 102: 2833:Spoilt vote 2596:Droop quota 2535:Schulze STV 2510:Rural–urban 2455:STAR voting 2351:Borda count 2107:1407.3247v1 1756:Consistency 1525:Candidate Y 1522:Candidate X 1519:Candidate C 1516:Candidate B 1513:Candidate A 1320:Candidate Y 1317:Candidate X 1314:Candidate C 1311:Candidate B 1308:Candidate A 1262:Total Votes 1134:Candidate Y 1131:Candidate X 1128:Candidate C 1125:Candidate B 1122:Candidate A 1005:Description 653:Single vote 556:Conditional 551:Coexistence 400:Quota Borda 390:Schulze STV 348:Closed list 291:STAR voting 236:Borda count 2896:Categories 2852:Comparison 2606:Hare quota 2556:Allocation 2542:Spare vote 2530:Hare-Clark 2500:Party-list 2241:2021-06-24 2204:1611.09928 2171:2022-05-11 2035:2022-05-11 1896:References 1710:Properties 1507:# of votes 1302:# of votes 1119:# of votes 758:Truncation 487:Cumulative 310:Party-list 85:By country 76:Comparison 2843:Unseating 2838:Sortition 2440:Plurality 2316:Economics 2223:2374-3468 2126:cite book 2008:152254976 1992:0003-0554 1931:1556-5068 665:Dual-vote 358:Panachage 353:Open list 343:List type 221:Plurality 117:Two-round 105:plurality 28:Economics 2710:Criteria 2663:Scorporo 2312:politics 2258:Archived 2235:Archived 2231:17538641 2165:Archived 2081:Archived 2029:Archived 1955:Archived 1939:53600917 1864:See also 1829:NP-hard 1742:Support 1075:and the 977:) is an 385:Hare STV 24:Politics 22:A joint 2882:Project 2573:D'Hondt 2525:CPO-STV 2483:Systems 2000:1950372 1689:37 5/6 1097:Example 395:CPO-STV 245:Baldwin 194:Schulze 189:Minimax 107:methods 2876:Portal 2813:Ballot 2589:Quotas 2318:series 2229:  2221:  2157:  2114:  2061:  2006:  1998:  1990:  1937:  1929:  1810:strong 1778:strong 1686:38 1/3 1679:60 1/3 1676:57 1/3 1052:where 999:Sweden 260:Coombs 30:series 2806:Other 2625:Mixed 2227:S2CID 2199:arXiv 2197:(1). 2102:arXiv 2004:S2CID 1996:JSTOR 1935:S2CID 1848:cand 1845:cand 1820:cand 969:) or 597:'MMP' 586:'AMS' 2314:and 2219:ISSN 2155:ISBN 2132:link 2112:ISBN 2059:ISBN 1988:ISSN 1927:ISSN 1652:1/2 1628:1/3 1605:1/2 1581:1/3 1559:1/2 1536:1/2 1423:1/2 1376:1/2 1354:1/2 1331:1/2 1142:112 967:SPAV 538:Non- 492:SNTV 81:List 38:and 26:and 2638:MMP 2209:doi 1980:doi 1919:doi 1533:112 1485:75 1328:112 1280:77 1271:126 1268:122 1265:116 1202:73 975:RAV 256:el. 241:el. 230:IRV 226:el. 2898:: 2879:— 2233:. 2225:. 2217:. 2207:. 2195:31 2193:. 2189:. 2163:. 2149:. 2128:}} 2124:{{ 2110:. 2027:. 2002:. 1994:. 1986:. 1976:44 1974:. 1933:. 1925:. 1917:. 1913:. 1857:P 1854:× 1851:× 1842:✓ 1839:× 1826:× 1823:✓ 1817:✓ 1814:× 1797:P 1794:✓ 1791:✓ 1788:✓ 1785:✓ 1782:✓ 1644:✓ 1620:✓ 1602:73 1482:76 1479:78 1474:61 1471:58 1447:1 1439:✓ 1415:✓ 1400:1 1397:73 1277:78 1274:82 1243:1 1238:✓ 1222:4 1217:✓ 1181:4 1162:6 1079:. 592:NZ 581:UK 157:US 146:UK 129:) 122:US 2293:e 2286:t 2279:v 2244:. 2211:: 2201:: 2174:. 2134:) 2120:. 2104:: 2067:. 2038:. 2010:. 1982:: 1941:. 1921:: 1699:3 1697:w 1664:✓ 1661:✓ 1649:1 1641:✓ 1638:✓ 1635:✓ 1625:4 1617:✓ 1614:✓ 1593:✓ 1590:✓ 1587:✓ 1584:✓ 1578:4 1567:✓ 1564:✓ 1556:6 1545:✓ 1542:✓ 1539:✓ 1495:2 1493:w 1459:✓ 1456:✓ 1444:1 1436:✓ 1433:✓ 1430:✓ 1420:4 1412:✓ 1409:✓ 1388:✓ 1385:✓ 1382:✓ 1379:✓ 1373:4 1362:✓ 1359:✓ 1351:6 1340:✓ 1337:✓ 1334:✓ 1290:1 1288:w 1255:✓ 1252:✓ 1235:✓ 1232:✓ 1229:✓ 1214:✓ 1211:✓ 1193:✓ 1190:✓ 1187:✓ 1184:✓ 1170:✓ 1167:✓ 1151:✓ 1148:✓ 1145:✓ 1054:s 1037:1 1034:+ 1031:s 1027:1 973:( 965:( 943:e 936:t 929:v 594:: 583:: 262:) 253:( 247:) 238:( 232:) 223:( 159:: 148:: 124:: 119:( 87:) 83:(

Index

Politics
Economics
Social choice
electoral systems

Social choice
Mechanism design
Comparative politics
Comparison
List
By country
Single-winner methods
plurality
First preference plurality (FPP)
Two-round
US
Jungle primary
Partisan primary
Instant-runoff
UK
Alternative vote
US
Ranked-choice (RCV)
Condorcet methods
Condorcet-IRV
Round-robin voting
Minimax
Schulze
Ranked pairs
Maximal lottery

Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.