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Rank-index method

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is an apportionment method where we begin by assigning every state its lower quota of seats. Then, we add seats one-by-one to the state with the highest votes-per-seat average, so long as adding an additional seat does not result in the state exceeding its upper quota. However, quota-capped divisor
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Moreover, quota-capped versions of other algorithms frequently violate the true quota in the presence of error (e.g. census miscounts). Jefferson's method frequently violates the true quota, even after being quota-capped, while Webster's method and Huntington-Hill perform well even without
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increases, the allocation of each agent weakly increases. This immediately follows from the iterative procedure.
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is not eligible to a seat in the current iteration, and some third party receives the seat instead.
1701: 812: 646: 299: 2941: 2551: 2104: 2059: 1949: 1914: 972: 843: 454: 238: 2509: 1978:, and apply the same method to their combined allocation, then the result is exactly the vector 921: 2910: 2819: 2776: 2696: 2618: 2541: 2526: 2484: 2379: 2338: 2306: 2279: 2240: 2196: 878: 848: 770: 707: 541: 268: 243: 226: 94: 2951: 2583: 2439: 2424: 2371: 2271: 2232: 1482: 959: 916: 807: 795: 509: 385: 211: 205: 187: 176: 171: 159: 120: 82: 1563: 1440: 1221: 2999: 2915: 2756: 2734: 2546: 2467: 2457: 2435: 1672: 1102: 947: 780: 635: 600: 521: 432: 335: 258: 200: 78: 102: 2814: 2519: 2479: 1922: 1666: 1645: 1539: 1518: 1420: 1292: 1272: 1252: 1098: 1076: 1048: 1022: 817: 757: 742: 553: 422: 397: 248: 942: 3019: 2558: 2331: 2299: 2189: 826: 526: 314: 152: 115: 90: 2573: 2514: 2375: 2275: 566: 330: 323: 253: 2259: 2220: 1669:
are a special case of rank-index methods: a divisor method with divisor function
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representing the total number of items to allocate. It is also called the
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Like all apportionment methods, the inputs of any rank-index method are:
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Because of the greater divisor, the upper quota of some other party
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Every rank-index method can be defined using a min-max inequality:
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is equivalent to a rank-index method with rank-index function
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to which items should be allocated. For example, these can be
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Fair Representation: Meeting the Ideal of One Man, One Vote
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Fair Representation: Meeting the Ideal of One Man, One Vote
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Fair Representation: Meeting the Ideal of One Man, One Vote
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At each iteration, allocate one item to an agent for whom
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is an allocation for the rank-index method with function
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may be too technical for most readers to understand
2330: 2298: 2188: 2114:However, quota-capped divisor methods violate the 2022: 1970: 1931: 1896: 1748: 1690: 1654: 1631: 1579: 1548: 1527: 1506: 1456: 1429: 1405: 1351: 1301: 1281: 1261: 1237: 1206: 1152: 1085: 1057: 2360:"Statistical Aspects of Equitable Apportionment" 1853: 1783: 2364:Journal of the American Statistical Association 2329:Balinski, Michel L.; Young, H. Peyton (1982). 2297:Balinski, Michel L.; Young, H. Peyton (1982). 2187:Balinski, Michel L.; Young, H. Peyton (1982). 2409: 1476:Every rank-index method is parametrized by a 990: 8: 2866:Independence of Smith-dominated alternatives 2258:Balinski, M. L.; Young, H. P. (1975-08-01). 2219:Balinski, M. L.; Young, H. P. (1977-12-01). 2103:Every quota-capped divisor method satisfies 2603: 2416: 2402: 2394: 1464:is the number of items allocated to agent 1269:, that is, the fraction of items to which 997: 983: 73: 2011: 1992: 1983: 1951: 1924: 1885: 1872: 1856: 1834: 1821: 1797: 1786: 1780: 1729: 1703: 1674: 1647: 1620: 1607: 1595: 1571: 1565: 1541: 1536:and decreasing in the current allocation 1520: 1514:, which is increasing in the entitlement 1484: 1448: 1442: 1422: 1391: 1381: 1370: 1364: 1343: 1324: 1318: 1294: 1274: 1254: 1229: 1223: 1192: 1182: 1171: 1165: 1141: 1122: 1113: 1078: 1050: 62:Learn how and when to remove this message 46:, without removing the technical details. 2221:"On Huntington Methods of Apportionment" 2861:Independence of irrelevant alternatives 2639:Sequential proportional approval voting 2174: 89: 2324: 2322: 1406:{\displaystyle \sum _{i=1}^{n}a_{i}=h} 1207:{\displaystyle \sum _{i=1}^{n}t_{i}=1} 2182: 2180: 2178: 2023:{\displaystyle (a_{1},\ldots ,a_{k})} 1153:{\displaystyle (t_{1},\ldots ,t_{n})} 44:make it understandable to non-experts 7: 2337:. New Haven: Yale University Press. 2305:. New Haven: Yale University Press. 2214: 2212: 2195:. New Haven: Yale University Press. 1639:is maximum (break ties arbitrarily). 2671:Indirect single transferable voting 2358:Spencer, Bruce D. (December 1985). 2260:"The Quota Method of Apportionment" 2225:SIAM Journal on Applied Mathematics 2152:Then, at the next iteration, party 2054:Every apportionment method that is 2037:Every apportionment method that is 1352:{\displaystyle a_{1},\ldots ,a_{n}} 1313:Its output is a vector of integers 1029:, since they generalize an idea by 14: 2264:The American Mathematical Monthly 1289:is entitled (out of the total of 2122:)—it is possible for a party to 2092:)—it is possible for a party to 966: 953: 941: 889:McKelvey–Schofield chaos theorem 535:Semi-proportional representation 167:First preference plurality (FPP) 23: 2782:Mixed ballot transferable vote 2376:10.1080/01621459.1985.10478188 2276:10.1080/00029890.1975.11993911 2126:a seat as a result of winning 2096:a seat as a result of winning 2017: 1985: 1891: 1865: 1846: 1814: 1743: 1737: 1720: 1708: 1685: 1679: 1632:{\displaystyle r(t_{i},a_{i})} 1626: 1600: 1501: 1489: 1147: 1115: 1025:. These have also been called 927:Harsanyi's utilitarian theorem 884:Moulin's impossibility theorem 849:Conflicting majorities paradox 16:Class of apportionment methods 1: 1749:{\displaystyle r(t,a)=t/d(a)} 753:Frustrated majorities paradox 2983:Comparison of voting systems 2825:Satisfaction approval voting 2810:Single non-transferable vote 2629:Proportional approval voting 2145:decreases. Therefore, party 2075:Quota-capped divisor methods 2070:must be a rank-index method. 2051:must be a rank-index method. 922:Condorcet dominance theorems 862:Social and collective choice 2589:Graduated majority judgment 2081:quota-capped divisor method 1971:{\displaystyle 1,\ldots ,k} 1942:Every rank-index method is 1913:Every rank-index method is 1093:representing the number of 588:By mechanism of combination 359:Proportional representation 3047: 2841:Condorcet winner criterion 2532:First-past-the-post voting 1031:Edward Vermilye Huntington 786:Multiple districts paradox 517:Fractional approval voting 505:Interactive representation 2996: 2988:Voting systems by country 2891:Mutual majority criterion 2846:Condorcet loser criterion 2792:Vote linkage mixed system 2704:Largest remainders method 2431: 2130:votes. This occurs when: 733:Paradoxes and pathologies 582:Mixed-member proportional 577:Mixed-member majoritarian 572:By results of combination 463:Approval-based committees 2881:Majority loser criterion 2767:Additional member system 2725:Hagenbach-Bischoff quota 2644:Single transferable vote 2569:Positional voting system 2505:Minimax Condorcet method 2463:Combined approval voting 1919:. This means that, when 912:Condorcet's jury theorem 713:Double simultaneous vote 688:Rural–urban proportional 683:Dual-member proportional 645: 634: 601:Parallel (superposition) 493:Fractional social choice 480:Expanding approvals rule 309: 294: 279: 210: 199: 175: 2906:Resolvability criterion 2896:Participation criterion 2871:Later-no-harm criterion 2687:Highest averages method 2120:population monotonicity 2116:participation criterion 2090:population monotonicity 2086:participation criterion 839:Tyranny of the majority 616:Fusion (majority bonus) 433:Quota-remainder methods 2947:First-preference votes 2886:Monotonicity criterion 2856:Independence of clones 2559:Simple majoritarianism 2024: 1972: 1933: 1906: 1898: 1750: 1692: 1656: 1633: 1581: 1550: 1529: 1508: 1507:{\displaystyle r(t,a)} 1458: 1431: 1407: 1386: 1353: 1303: 1283: 1263: 1239: 1208: 1187: 1154: 1108:A vector of fractions 1087: 1059: 973:Mathematics portal 879:Majority impossibility 868:Impossibility theorems 664:Negative vote transfer 485:Method of equal shares 106: 3031:Apportionment methods 3026:Mathematical theorems 2851:Consistency criterion 2772:Alternative vote plus 2537:Instant-runoff voting 2025: 1973: 1934: 1899: 1774: 1751: 1693: 1657: 1634: 1587:to 0 for all parties. 1582: 1580:{\displaystyle a_{i}} 1551: 1530: 1509: 1459: 1457:{\displaystyle a_{i}} 1432: 1408: 1366: 1354: 1304: 1284: 1264: 1240: 1238:{\displaystyle t_{i}} 1209: 1167: 1155: 1088: 1060: 1019:apportionment methods 776:Best-is-worst paradox 765:Pathological response 500:Direct representation 153:Single-winner methods 105: 2921:Seats-to-votes ratio 2692:Webster/Sainte-LaguĂ« 2084:methods violate the 1982: 1950: 1923: 1779: 1702: 1691:{\displaystyle d(a)} 1673: 1646: 1594: 1564: 1540: 1519: 1483: 1441: 1421: 1363: 1317: 1293: 1273: 1253: 1222: 1164: 1112: 1077: 1049: 1021:that generalize the 1011:apportionment theory 960:Economics portal 907:Median voter theorem 126:Comparative politics 2901:Plurality criterion 2500:Kemeny–Young method 1760:Min-max formulation 1478:rank-index function 1472:Iterative procedure 1073:A positive integer 1045:A positive integer 948:Politics portal 659:Vote linkage system 630:Seat linkage system 217:Ranked-choice (RCV) 2942:Election threshold 2876:Majority criterion 2552:Supplementary vote 2105:house monotonicity 2020: 1968: 1929: 1894: 1861: 1810: 1746: 1688: 1652: 1629: 1577: 1546: 1525: 1504: 1454: 1427: 1403: 1349: 1299: 1279: 1259: 1235: 1204: 1150: 1083: 1055: 1027:Huntington methods 1015:rank-index methods 844:Discursive dilemma 803:Lesser evil voting 678:Supermixed systems 381:Largest remainders 239:Round-robin voting 107: 3013: 3012: 2911:Reversal symmetry 2820:Cumulative voting 2802:Semi-proportional 2777:Mixed single vote 2743: 2742: 2619:Mixed single vote 2527:Exhaustive ballot 2490:Copeland's method 2485:Condorcet methods 2425:Electoral systems 1932:{\displaystyle h} 1852: 1782: 1772:, if-and-only-if: 1655:{\displaystyle h} 1549:{\displaystyle a} 1528:{\displaystyle t} 1430:{\displaystyle h} 1302:{\displaystyle h} 1282:{\displaystyle i} 1262:{\displaystyle i} 1103:political parties 1086:{\displaystyle n} 1058:{\displaystyle h} 1007: 1006: 894:Gibbard's theorem 834:Dominance paradox 771:Perverse response 475:Phragmen's method 341:Majority judgment 269:Positional voting 227:Condorcet methods 95:electoral systems 72: 71: 64: 3038: 2952:Liquid democracy 2604: 2584:Two-round system 2495:Dodgson's method 2418: 2411: 2404: 2395: 2388: 2387: 2370:(392): 815–822. 2355: 2349: 2348: 2336: 2326: 2317: 2316: 2304: 2294: 2288: 2287: 2255: 2249: 2248: 2216: 2207: 2206: 2194: 2184: 2138:gets more votes. 2029: 2027: 2026: 2021: 2016: 2015: 1997: 1996: 1977: 1975: 1974: 1969: 1938: 1936: 1935: 1930: 1903: 1901: 1900: 1895: 1890: 1889: 1877: 1876: 1860: 1839: 1838: 1826: 1825: 1809: 1802: 1801: 1755: 1753: 1752: 1747: 1733: 1697: 1695: 1694: 1689: 1661: 1659: 1658: 1653: 1638: 1636: 1635: 1630: 1625: 1624: 1612: 1611: 1586: 1584: 1583: 1578: 1576: 1575: 1555: 1553: 1552: 1547: 1534: 1532: 1531: 1526: 1513: 1511: 1510: 1505: 1463: 1461: 1460: 1455: 1453: 1452: 1436: 1434: 1433: 1428: 1412: 1410: 1409: 1404: 1396: 1395: 1385: 1380: 1358: 1356: 1355: 1350: 1348: 1347: 1329: 1328: 1308: 1306: 1305: 1300: 1288: 1286: 1285: 1280: 1268: 1266: 1265: 1260: 1244: 1242: 1241: 1236: 1234: 1233: 1213: 1211: 1210: 1205: 1197: 1196: 1186: 1181: 1159: 1157: 1156: 1151: 1146: 1145: 1127: 1126: 1092: 1090: 1089: 1084: 1064: 1062: 1061: 1056: 1037:Input and output 999: 992: 985: 971: 970: 958: 957: 946: 945: 901:Positive results 796:Strategic voting 693:Majority jackpot 650: 639: 510:Liquid democracy 386:National remnant 376:Highest averages 313: 298: 283: 215: 206:Alternative vote 204: 188:Partisan primary 180: 121:Mechanism design 74: 67: 60: 56: 53: 47: 27: 26: 19: 3046: 3045: 3041: 3040: 3039: 3037: 3036: 3035: 3016: 3015: 3014: 3009: 2992: 2971: 2925: 2916:Smith criterion 2829: 2796: 2757:Parallel voting 2739: 2735:Imperiali quota 2708: 2675: 2593: 2547:Contingent vote 2510:Nanson's method 2468:Unified primary 2458:Approval voting 2444: 2427: 2422: 2392: 2391: 2357: 2356: 2352: 2345: 2328: 2327: 2320: 2313: 2296: 2295: 2291: 2257: 2256: 2252: 2237:10.1137/0133043 2218: 2217: 2210: 2203: 2186: 2185: 2176: 2171: 2077: 2007: 1988: 1980: 1979: 1948: 1947: 1921: 1920: 1911: 1881: 1868: 1830: 1817: 1793: 1777: 1776: 1762: 1700: 1699: 1671: 1670: 1667:Divisor methods 1644: 1643: 1616: 1603: 1592: 1591: 1567: 1562: 1561: 1560:Initially, set 1538: 1537: 1517: 1516: 1481: 1480: 1474: 1444: 1439: 1438: 1419: 1418: 1387: 1361: 1360: 1339: 1320: 1315: 1314: 1291: 1290: 1271: 1270: 1251: 1250: 1245:represents the 1225: 1220: 1219: 1214:, representing 1188: 1162: 1161: 1137: 1118: 1110: 1109: 1075: 1074: 1047: 1046: 1039: 1003: 965: 964: 952: 940: 932: 931: 898: 874:Arrow's theorem 864: 854: 853: 822: 792: 781:No-show paradox 762: 748:Cloning paradox 738:Spoiler effects 735: 725: 724: 699: 586: 569: 559: 558: 531: 522:Maximal lottery 489: 470:Thiele's method 459: 429: 361: 351: 350: 336:Approval voting 324:Cardinal voting 320: 265: 259:Maximal lottery 223: 155: 145: 68: 57: 51: 48: 40:help improve it 37: 28: 24: 17: 12: 11: 5: 3044: 3042: 3034: 3033: 3028: 3018: 3017: 3011: 3010: 2997: 2994: 2993: 2991: 2990: 2985: 2979: 2977: 2973: 2972: 2970: 2969: 2964: 2959: 2954: 2949: 2944: 2939: 2933: 2931: 2927: 2926: 2924: 2923: 2918: 2913: 2908: 2903: 2898: 2893: 2888: 2883: 2878: 2873: 2868: 2863: 2858: 2853: 2848: 2843: 2837: 2835: 2831: 2830: 2828: 2827: 2822: 2817: 2815:Limited voting 2812: 2806: 2804: 2798: 2797: 2795: 2794: 2789: 2784: 2779: 2774: 2769: 2764: 2759: 2753: 2751: 2745: 2744: 2741: 2740: 2738: 2737: 2732: 2727: 2722: 2716: 2714: 2710: 2709: 2707: 2706: 2701: 2700: 2699: 2694: 2683: 2681: 2677: 2676: 2674: 2673: 2668: 2663: 2662: 2661: 2656: 2651: 2641: 2636: 2631: 2626: 2621: 2616: 2610: 2608: 2601: 2595: 2594: 2592: 2591: 2586: 2581: 2576: 2571: 2566: 2561: 2556: 2555: 2554: 2549: 2544: 2542:Coombs' method 2534: 2529: 2524: 2523: 2522: 2520:Schulze method 2517: 2512: 2507: 2502: 2497: 2492: 2482: 2480:Bucklin voting 2477: 2472: 2471: 2470: 2465: 2454: 2452: 2446: 2445: 2432: 2429: 2428: 2423: 2421: 2420: 2413: 2406: 2398: 2390: 2389: 2350: 2343: 2318: 2311: 2289: 2270:(7): 701–730. 2250: 2231:(4): 607–618. 2208: 2201: 2173: 2172: 2170: 2167: 2162: 2161: 2150: 2139: 2076: 2073: 2072: 2071: 2061:house-monotone 2052: 2019: 2014: 2010: 2006: 2003: 2000: 1995: 1991: 1987: 1967: 1964: 1961: 1958: 1955: 1928: 1916:house-monotone 1910: 1907: 1893: 1888: 1884: 1880: 1875: 1871: 1867: 1864: 1859: 1855: 1851: 1848: 1845: 1842: 1837: 1833: 1829: 1824: 1820: 1816: 1813: 1808: 1805: 1800: 1796: 1792: 1789: 1785: 1761: 1758: 1745: 1742: 1739: 1736: 1732: 1728: 1725: 1722: 1719: 1716: 1713: 1710: 1707: 1687: 1684: 1681: 1678: 1664: 1663: 1651: 1640: 1628: 1623: 1619: 1615: 1610: 1606: 1602: 1599: 1588: 1574: 1570: 1545: 1524: 1503: 1500: 1497: 1494: 1491: 1488: 1473: 1470: 1451: 1447: 1426: 1402: 1399: 1394: 1390: 1384: 1379: 1376: 1373: 1369: 1346: 1342: 1338: 1335: 1332: 1327: 1323: 1311: 1310: 1298: 1278: 1258: 1232: 1228: 1203: 1200: 1195: 1191: 1185: 1180: 1177: 1174: 1170: 1149: 1144: 1140: 1136: 1133: 1130: 1125: 1121: 1117: 1106: 1099:federal states 1082: 1070: 1069: 1054: 1038: 1035: 1023:divisor method 1005: 1004: 1002: 1001: 994: 987: 979: 976: 975: 963: 962: 950: 937: 934: 933: 930: 929: 924: 919: 914: 909: 897: 896: 891: 886: 881: 876: 865: 860: 859: 856: 855: 852: 851: 846: 841: 836: 821: 820: 818:Turkey-raising 815: 810: 805: 791: 790: 789: 788: 778: 773: 761: 760: 758:Center squeeze 755: 750: 745: 743:Spoiler effect 736: 731: 730: 727: 726: 723: 722: 717: 716: 715: 702:By ballot type 698: 697: 696: 695: 690: 685: 675: 674: 673: 672: 671: 666: 656: 655: 654: 643: 620: 619: 618: 613: 608: 603: 585: 584: 579: 570: 565: 564: 561: 560: 557: 556: 554:Limited voting 551: 550: 549: 530: 529: 524: 519: 514: 513: 512: 507: 488: 487: 482: 477: 472: 458: 457: 452: 447: 442: 428: 427: 426: 425: 423:Localized list 420: 415: 410: 405: 395: 394: 393: 391:Biproportional 388: 383: 378: 362: 357: 356: 353: 352: 349: 348: 343: 338: 333: 319: 318: 303: 288: 264: 263: 262: 261: 256: 251: 246: 236: 222: 221: 220: 219: 208: 195:Instant-runoff 192: 191: 190: 182:Jungle primary 169: 158:Single vote - 156: 151: 150: 147: 146: 144: 143: 133: 128: 123: 118: 112: 109: 108: 98: 97: 87: 86: 70: 69: 31: 29: 22: 15: 13: 10: 9: 6: 4: 3: 2: 3043: 3032: 3029: 3027: 3024: 3023: 3021: 3008: 3007: 3002: 3001: 2995: 2989: 2986: 2984: 2981: 2980: 2978: 2974: 2968: 2965: 2963: 2960: 2958: 2955: 2953: 2950: 2948: 2945: 2943: 2940: 2938: 2935: 2934: 2932: 2928: 2922: 2919: 2917: 2914: 2912: 2909: 2907: 2904: 2902: 2899: 2897: 2894: 2892: 2889: 2887: 2884: 2882: 2879: 2877: 2874: 2872: 2869: 2867: 2864: 2862: 2859: 2857: 2854: 2852: 2849: 2847: 2844: 2842: 2839: 2838: 2836: 2832: 2826: 2823: 2821: 2818: 2816: 2813: 2811: 2808: 2807: 2805: 2803: 2799: 2793: 2790: 2788: 2785: 2783: 2780: 2778: 2775: 2773: 2770: 2768: 2765: 2763: 2760: 2758: 2755: 2754: 2752: 2750: 2746: 2736: 2733: 2731: 2728: 2726: 2723: 2721: 2718: 2717: 2715: 2711: 2705: 2702: 2698: 2695: 2693: 2690: 2689: 2688: 2685: 2684: 2682: 2678: 2672: 2669: 2667: 2664: 2660: 2657: 2655: 2652: 2650: 2647: 2646: 2645: 2642: 2640: 2637: 2635: 2632: 2630: 2627: 2625: 2622: 2620: 2617: 2615: 2612: 2611: 2609: 2605: 2602: 2600: 2596: 2590: 2587: 2585: 2582: 2580: 2577: 2575: 2572: 2570: 2567: 2565: 2562: 2560: 2557: 2553: 2550: 2548: 2545: 2543: 2540: 2539: 2538: 2535: 2533: 2530: 2528: 2525: 2521: 2518: 2516: 2513: 2511: 2508: 2506: 2503: 2501: 2498: 2496: 2493: 2491: 2488: 2487: 2486: 2483: 2481: 2478: 2476: 2473: 2469: 2466: 2464: 2461: 2460: 2459: 2456: 2455: 2453: 2451: 2450:Single-winner 2447: 2443: 2441: 2437: 2430: 2426: 2419: 2414: 2412: 2407: 2405: 2400: 2399: 2396: 2385: 2381: 2377: 2373: 2369: 2365: 2361: 2354: 2351: 2346: 2344:0-300-02724-9 2340: 2335: 2334: 2325: 2323: 2319: 2314: 2312:0-300-02724-9 2308: 2303: 2302: 2293: 2290: 2285: 2281: 2277: 2273: 2269: 2265: 2261: 2254: 2251: 2246: 2242: 2238: 2234: 2230: 2226: 2222: 2215: 2213: 2209: 2204: 2202:0-300-02724-9 2198: 2193: 2192: 2183: 2181: 2179: 2175: 2168: 2166: 2159: 2155: 2151: 2148: 2144: 2140: 2137: 2133: 2132: 2131: 2129: 2125: 2121: 2118:(also called 2117: 2112: 2110: 2106: 2101: 2099: 2095: 2091: 2088:(also called 2087: 2082: 2074: 2069: 2068: 2063: 2062: 2057: 2053: 2050: 2049: 2044: 2040: 2036: 2035: 2034: 2031: 2012: 2008: 2004: 2001: 1998: 1993: 1989: 1965: 1962: 1959: 1956: 1953: 1945: 1940: 1926: 1918: 1917: 1908: 1905: 1886: 1882: 1878: 1873: 1869: 1862: 1857: 1849: 1843: 1840: 1835: 1831: 1827: 1822: 1818: 1811: 1806: 1803: 1798: 1794: 1790: 1787: 1773: 1771: 1767: 1759: 1757: 1740: 1734: 1730: 1726: 1723: 1717: 1714: 1711: 1705: 1682: 1676: 1668: 1649: 1641: 1621: 1617: 1613: 1608: 1604: 1597: 1589: 1572: 1568: 1559: 1558: 1557: 1543: 1535: 1522: 1498: 1495: 1492: 1486: 1479: 1471: 1469: 1467: 1449: 1445: 1424: 1416: 1415:apportionment 1400: 1397: 1392: 1388: 1382: 1377: 1374: 1371: 1367: 1344: 1340: 1336: 1333: 1330: 1325: 1321: 1296: 1276: 1256: 1248: 1230: 1226: 1217: 1201: 1198: 1193: 1189: 1183: 1178: 1175: 1172: 1168: 1142: 1138: 1134: 1131: 1128: 1123: 1119: 1107: 1104: 1100: 1096: 1080: 1072: 1071: 1068: 1052: 1044: 1043: 1042: 1036: 1034: 1032: 1028: 1024: 1020: 1017:are a set of 1016: 1012: 1000: 995: 993: 988: 986: 981: 980: 978: 977: 974: 969: 961: 956: 951: 949: 944: 939: 938: 936: 935: 928: 925: 923: 920: 918: 917:May's theorem 915: 913: 910: 908: 905: 904: 903: 902: 895: 892: 890: 887: 885: 882: 880: 877: 875: 872: 871: 870: 869: 863: 858: 857: 850: 847: 845: 842: 840: 837: 835: 832: 831: 830: 829: 828: 827:majority rule 825:Paradoxes of 819: 816: 814: 811: 809: 806: 804: 801: 800: 799: 798: 797: 787: 784: 783: 782: 779: 777: 774: 772: 769: 768: 767: 766: 759: 756: 754: 751: 749: 746: 744: 741: 740: 739: 734: 729: 728: 721: 718: 714: 711: 710: 709: 706: 705: 704: 703: 694: 691: 689: 686: 684: 681: 680: 679: 676: 670: 667: 665: 662: 661: 660: 657: 653: 648: 644: 642: 637: 633: 632: 631: 628: 627: 626: 625: 621: 617: 614: 612: 609: 607: 604: 602: 599: 598: 597: 596: 591: 590: 589: 583: 580: 578: 575: 574: 573: 568: 567:Mixed systems 563: 562: 555: 552: 548: 545: 544: 543: 540: 539: 538: 537: 536: 528: 527:Random ballot 525: 523: 520: 518: 515: 511: 508: 506: 503: 502: 501: 498: 497: 496: 495: 494: 486: 483: 481: 478: 476: 473: 471: 468: 467: 466: 465: 464: 456: 453: 451: 448: 446: 443: 441: 438: 437: 436: 435: 434: 424: 421: 419: 416: 414: 411: 409: 406: 404: 401: 400: 399: 396: 392: 389: 387: 384: 382: 379: 377: 374: 373: 372: 371:Apportionment 369: 368: 367: 366: 360: 355: 354: 347: 344: 342: 339: 337: 334: 332: 329: 328: 327: 326: 325: 316: 312: 307: 306:Antiplurality 304: 301: 297: 292: 289: 286: 282: 277: 274: 273: 272: 271: 270: 260: 257: 255: 252: 250: 247: 245: 242: 241: 240: 237: 235: 234:Condorcet-IRV 232: 231: 230: 229: 228: 218: 213: 209: 207: 202: 198: 197: 196: 193: 189: 186: 185: 183: 178: 173: 170: 168: 165: 164: 163: 161: 154: 149: 148: 141: 137: 134: 132: 129: 127: 124: 122: 119: 117: 116:Social choice 114: 113: 111: 110: 104: 100: 99: 96: 92: 91:Social choice 88: 84: 80: 76: 75: 66: 63: 55: 45: 41: 35: 32:This article 30: 21: 20: 3004: 2998: 2614:Mixed-member 2599:Proportional 2574:Score voting 2515:Ranked pairs 2434:Part of the 2433: 2367: 2363: 2353: 2332: 2300: 2292: 2267: 2263: 2253: 2228: 2224: 2190: 2165:quota-caps. 2163: 2157: 2153: 2146: 2142: 2135: 2127: 2123: 2113: 2102: 2097: 2093: 2080: 2078: 2065: 2060: 2055: 2046: 2042: 2038: 2032: 1943: 1941: 1915: 1912: 1775: 1769: 1765: 1763: 1665: 1515: 1477: 1475: 1465: 1414: 1413:, called an 1312: 1216:entitlements 1215: 1094: 1066: 1040: 1026: 1014: 1008: 900: 899: 866: 824: 823: 808:Exaggeration 794: 793: 764: 763: 737: 701: 700: 669:Mixed ballot 624:Compensatory 622: 595:compensatory 592: 587: 571: 533: 532: 491: 490: 461: 460: 431: 430: 418:List-free PR 363: 331:Score voting 322: 321: 267: 266: 254:Ranked pairs 225: 224: 157: 58: 52:January 2024 49: 33: 2957:Spoilt vote 2720:Droop quota 2659:Schulze STV 2634:Rural–urban 2579:STAR voting 2475:Borda count 1662:iterations. 1642:Stop after 1247:entitlement 1067:house size. 708:Single vote 611:Conditional 606:Coexistence 455:Quota Borda 445:Schulze STV 403:Closed list 346:STAR voting 291:Borda count 3020:Categories 2976:Comparison 2730:Hare quota 2680:Allocation 2666:Spare vote 2654:Hare-Clark 2624:Party-list 2169:References 2109:quota rule 2033:Moreover: 1909:Properties 813:Truncation 542:Cumulative 365:Party-list 140:By country 131:Comparison 2967:Unseating 2962:Sortition 2564:Plurality 2440:Economics 2384:0162-1459 2284:0002-9890 2245:0036-1399 2043:symmetric 2002:… 1960:… 1850:≥ 1841:− 1368:∑ 1334:… 1249:of agent 1169:∑ 1132:… 720:Dual-vote 413:Panachage 408:Open list 398:List type 276:Plurality 172:Two-round 160:plurality 83:Economics 2834:Criteria 2787:Scorporo 2436:politics 2067:balanced 2048:balanced 1437:, where 440:Hare STV 79:Politics 77:A joint 3006:Project 2697:D'Hondt 2649:CPO-STV 2607:Systems 2100:votes. 2056:uniform 2039:uniform 1944:uniform 450:CPO-STV 300:Baldwin 249:Schulze 244:Minimax 162:methods 38:Please 3000:Portal 2937:Ballot 2713:Quotas 2442:series 2382:  2341:  2309:  2282:  2243:  2199:  2134:Party 1095:agents 315:Coombs 85:series 2930:Other 2749:Mixed 1359:with 1160:with 652:'MMP' 641:'AMS' 2438:and 2380:ISSN 2339:ISBN 2307:ISBN 2280:ISSN 2241:ISSN 2197:ISBN 2128:more 2124:lose 2098:more 2094:lose 2064:and 2045:and 1804:> 593:Non- 547:SNTV 136:List 93:and 81:and 2762:MMP 2372:doi 2272:doi 2233:doi 1854:max 1784:min 1417:of 1101:or 1033:. 1009:In 311:el. 296:el. 285:IRV 281:el. 42:to 3022:: 3003:— 2378:. 2368:80 2366:. 2362:. 2321:^ 2278:. 2268:82 2266:. 2262:. 2239:. 2229:33 2227:. 2223:. 2211:^ 2177:^ 2111:. 2079:A 2058:, 2041:, 1756:. 1468:. 1309:). 1218:- 1013:, 647:NZ 636:UK 212:US 201:UK 184:) 177:US 2417:e 2410:t 2403:v 2386:. 2374:: 2347:. 2315:. 2286:. 2274:: 2247:. 2235:: 2205:. 2160:. 2158:i 2154:j 2147:j 2143:j 2136:i 2018:) 2013:k 2009:a 2005:, 1999:, 1994:1 1990:a 1986:( 1966:k 1963:, 1957:, 1954:1 1927:h 1904:. 1892:) 1887:i 1883:a 1879:, 1874:i 1870:t 1866:( 1863:r 1858:i 1847:) 1844:1 1836:i 1832:a 1828:, 1823:i 1819:t 1815:( 1812:r 1807:0 1799:i 1795:a 1791:: 1788:i 1770:r 1766:a 1744:) 1741:a 1738:( 1735:d 1731:/ 1727:t 1724:= 1721:) 1718:a 1715:, 1712:t 1709:( 1706:r 1686:) 1683:a 1680:( 1677:d 1650:h 1627:) 1622:i 1618:a 1614:, 1609:i 1605:t 1601:( 1598:r 1573:i 1569:a 1544:a 1523:t 1502:) 1499:a 1496:, 1493:t 1490:( 1487:r 1466:i 1450:i 1446:a 1425:h 1401:h 1398:= 1393:i 1389:a 1383:n 1378:1 1375:= 1372:i 1345:n 1341:a 1337:, 1331:, 1326:1 1322:a 1297:h 1277:i 1257:i 1231:i 1227:t 1202:1 1199:= 1194:i 1190:t 1184:n 1179:1 1176:= 1173:i 1148:) 1143:n 1139:t 1135:, 1129:, 1124:1 1120:t 1116:( 1105:. 1081:n 1053:h 998:e 991:t 984:v 649:: 638:: 317:) 308:( 302:) 293:( 287:) 278:( 214:: 203:: 179:: 174:( 142:) 138:( 65:) 59:( 54:) 50:( 36:.

Index

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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

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