Knowledge (XXG)

Tracking error

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1138: 891: 62:. Tracking error measures the deviation from the benchmark: an index fund has a near-zero tracking error, while an actively managed portfolio would normally have a higher tracking error. Thus the tracking error does not include any risk (return) that is merely a function of the market's movement. In addition to 636:
Under the assumption of normality of returns, an active risk of x per cent would mean that approximately 2/3 of the portfolio's active returns (one standard deviation from the mean) can be expected to fall between +x and -x per cent of the mean excess return and about 95% of the portfolio's active
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If tracking error is measured historically, it is called 'realized' or 'ex post' tracking error. If a model is used to predict tracking error, it is called 'ex ante' tracking error. Ex-post tracking error is more useful for reporting performance, whereas ex-ante tracking error is generally used by
98:. In a factor model of a portfolio, the non-systematic risk (i.e., the standard deviation of the residuals) is called "tracking error" in the investment field. The latter way to compute the tracking error complements the formulas below but results can vary (sometimes by a factor of 2). 361: 627: 1133:{\displaystyle {\begin{aligned}\min _{w}&\quad \omega ^{2}\\{\text{s.t.}}&\quad w_{j}\leq y_{j},\quad \sum _{j=1}^{N}y_{j}\leq K\\&\quad \ell _{j}y_{j}\leq w_{j}\leq u_{j}y_{j},\quad y_{j}\in \{0,1\},\quad \ell _{j},\;u_{j}\geq 0\end{aligned}}} 1253: 463: 116: 781: 896: 1170: 450: 697: 404: 838: 814: 1165: 882: 862: 1345: 702: 356:{\displaystyle TE=\omega ={\sqrt {\operatorname {Var} (r_{p}-r_{b})}}={\sqrt {{E}-({E})^{2}}}={\sqrt {(w_{p}-w_{b})^{T}\Sigma (w_{p}-w_{b})}}} 1792: 2018: 2008: 1280: 659:
of an index or other benchmark, and thus reflect tracking errors relative to short positions in the underlying index or benchmark.
622:{\displaystyle \max _{w}\;\mu ^{T}(w-w_{b}),\quad {\text{s.t.}}\;(w-w_{b})^{T}\Sigma (w-w_{b})\leq \omega ^{2},\;Ax\leq b,\;Cx=d} 637:
returns (two standard deviations from the mean) can be expected to fall between +2x and -2x per cent of the mean excess return.
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portfolio managers to control risk. Various types of ex-ante tracking error models exist, from simple equity models which use
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they are attempting to replicate, and this problem may be solved using standard optimization techniques. To begin, define
457: 2013: 1338: 652: 1625: 1517: 1689: 1777: 1358: 453: 1635: 1600: 1605: 43:; it indicates how closely a portfolio follows the index to which it is benchmarked. The best measure is the 1944: 1665: 1650: 1592: 1331: 817: 54:, are expected to replicate, before trading and other costs, the returns of an index exactly, while others ' 1640: 1318: 1308: 1982: 1884: 1857: 1842: 1610: 1465: 1386: 1248:{\displaystyle y_{j}={\begin{cases}1,\quad &w_{j}>0\\0,\quad &{\text{otherwise}}\end{cases}}} 885: 456:
problem of maximizing the return, subject to tracking error and linear constraints, may be solved using
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is the active return, i.e., the difference between the portfolio return and the benchmark return and
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is the logical condition of whether or not an asset is included in the index fund, and is defined as:
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investable assets in the index, it is sometimes better practice to only invest in a subset
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Many portfolios are managed to a benchmark, typically an index. Some portfolios, notably
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for the assets in the index. While creating an index fund could involve holding all
1914: 1899: 1675: 1537: 1498: 1964: 1924: 1670: 1655: 1568: 1455: 1433: 1421: 1373: 1275:. Mathematics, Finance and Risk. Cambridge University Press. pp. 178–180. 1547: 1527: 1441: 1437: 1299: 646: 51: 1894: 668:
Index funds are expected to minimize the tracking error with respect to the
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is the vector of active portfolio weights relative to the benchmark. The
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Dividing portfolio active return by portfolio tracking error gives the
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is the vector of active weights for each asset relative to the
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of the difference between the portfolio and index returns.
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of the assets. These considerations lead to the following
776:{\displaystyle \omega ^{2}=(w-w_{b})^{T}\Sigma (w-w_{b})} 66:(return) from specific stock selection or industry and 1173: 1146: 894: 870: 850: 826: 789: 705: 678: 466: 412: 372: 119: 1730: 1591: 1556: 1508: 1420: 1372: 1365: 1309:Tracking error: A hidden cost of passive investing 1247: 1159: 1132: 876: 856: 832: 808: 775: 691: 621: 444: 398: 355: 900: 468: 81:, which is a risk adjusted performance measure. 70:"betas", it can also include risk (return) from 1339: 649:are expected to have minimal tracking errors. 94:as a primary determinant to more complicated 8: 1089: 1077: 1369: 1346: 1332: 1324: 1271:Cornuejols, Gerard; Tütüncü, Reha (2007). 1109: 886:mixed-integer quadratic programming (MIQP) 606: 590: 519: 477: 106:The ex-post tracking error formula is the 1233: 1208: 1187: 1178: 1172: 1151: 1145: 1114: 1100: 1068: 1054: 1044: 1031: 1018: 1008: 986: 976: 965: 951: 938: 926: 916: 903: 895: 893: 869: 849: 825: 800: 788: 764: 742: 732: 710: 704: 683: 677: 581: 565: 543: 533: 514: 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investment risk 2009:Financial risk management 1973: 1359:financial risk management 1636:First-hitting-time model 1601:Arbitrage pricing theory 1945:Stress test (financial) 1651:Modern portfolio theory 833:{\displaystyle \Sigma } 809:{\displaystyle w-w_{b}} 1249: 1161: 1134: 981: 878: 858: 834: 810: 777: 693: 623: 446: 400: 357: 39:decisions made by the 1983:Investment management 1885:Investment management 1611:Replicating portfolio 1387:Sovereign credit risk 1250: 1162: 1160:{\displaystyle y_{j}} 1135: 961: 879: 859: 835: 811: 778: 694: 624: 447: 401: 358: 1988:Mathematical finance 1920:Risk-return spectrum 1910:Mathematical finance 1865:Fundamental analysis 1798:Exchange traded fund 1382:Consumer credit risk 1171: 1144: 892: 868: 848: 824: 787: 703: 676: 464: 410: 370: 117: 33:investment portfolio 2014:Convex optimization 1978:Financial economics 1935:Statistical finance 1701:Value-at-Risk (VaR) 1606:Black–Scholes model 1446:Holding period risk 664:Index fund creation 1955:Structured product 1950:Structured finance 1930:Speculative attack 1616:Cash flow matching 1579:Non-financial risk 1476:Interest rate risk 1402:Concentration risk 1245: 1240: 1157: 1130: 1128: 908: 874: 854: 830: 806: 773: 689: 619: 476: 442: 396: 353: 108:standard deviation 45:standard deviation 1996: 1995: 1768:Corporate finance 1763:Capital structure 1717:Cash flow at risk 1713:Liquidity at risk 1686:Survival analysis 1587: 1586: 1533:Reputational risk 1407:Credit derivative 1236: 929: 899: 877:{\displaystyle K} 857:{\displaystyle N} 842:covariance matrix 517: 467: 351: 276: 172: 79:information ratio 41:portfolio manager 37:active management 2026: 1870:Growth investing 1788:Enterprise value 1738:Asset allocation 1721:Earnings at risk 1703:and extensions ( 1646:Market portfolio 1510:Operational risk 1495:Refinancing risk 1370: 1348: 1341: 1334: 1325: 1287: 1286: 1268: 1254: 1252: 1251: 1246: 1244: 1243: 1237: 1234: 1213: 1212: 1183: 1182: 1166: 1164: 1163: 1158: 1156: 1155: 1139: 1137: 1136: 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concepts 1728: 1727: 1725: 1724: 1709:Margin at risk 1705:Profit at risk 1698: 1696:Tracking error 1693: 1683: 1678: 1673: 1668: 1666:Risk-free rate 1663: 1658: 1653: 1648: 1643: 1638: 1633: 1628: 1623: 1618: 1613: 1608: 1603: 1597: 1595: 1589: 1588: 1585: 1584: 1582: 1581: 1576: 1571: 1566: 1564:Execution risk 1560: 1558: 1554: 1553: 1551: 1550: 1545: 1543:Political risk 1540: 1535: 1530: 1525: 1520: 1514: 1512: 1506: 1505: 1503: 1502: 1491:Liquidity risk 1488: 1483: 1481:Inflation risk 1478: 1473: 1471:Margining risk 1468: 1463: 1461:Valuation risk 1458: 1453: 1430:Commodity risk 1426: 1424: 1418: 1417: 1415: 1414: 1412:Securitization 1409: 1404: 1399: 1394: 1389: 1384: 1378: 1376: 1367: 1363: 1362: 1355:Financial risk 1353: 1351: 1350: 1343: 1336: 1328: 1322: 1321: 1316: 1314:Tracking error 1311: 1306: 1300:Tracking Error 1295: 1294:External links 1292: 1289: 1288: 1282:978-0521861700 1281: 1262: 1261: 1259: 1256: 1242: 1232: 1229: 1226: 1223: 1222: 1219: 1216: 1211: 1207: 1203: 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197: 193: 189: 186: 182: 176: 171: 166: 162: 158: 153: 149: 145: 142: 139: 134: 131: 128: 125: 122: 103: 100: 86: 83: 60:active returns 25:tracking error 15: 13: 10: 9: 6: 4: 3: 2: 2031: 2020: 2017: 2015: 2012: 2010: 2007: 2006: 2004: 1989: 1986: 1984: 1981: 1979: 1976: 1975: 1972: 1966: 1963: 1961: 1960:Systemic risk 1958: 1956: 1953: 1951: 1948: 1946: 1943: 1941: 1938: 1936: 1933: 1931: 1928: 1926: 1923: 1921: 1918: 1916: 1913: 1911: 1908: 1906: 1903: 1901: 1898: 1896: 1893: 1891: 1888: 1886: 1883: 1881: 1878: 1876: 1873: 1871: 1868: 1866: 1863: 1859: 1856: 1854: 1851: 1849: 1846: 1844: 1841: 1839: 1836: 1834: 1831: 1829: 1826: 1824: 1821: 1819: 1816: 1814: 1811: 1810: 1809: 1806: 1804: 1801: 1799: 1796: 1794: 1791: 1789: 1786: 1784: 1781: 1779: 1776: 1774: 1771: 1769: 1766: 1764: 1761: 1759: 1758:Capital asset 1756: 1754: 1751: 1749: 1748:Asset pricing 1746: 1744: 1741: 1739: 1736: 1735: 1733: 1729: 1722: 1718: 1714: 1710: 1706: 1702: 1699: 1697: 1694: 1691: 1687: 1684: 1682: 1681:Sortino ratio 1679: 1677: 1674: 1672: 1669: 1667: 1664: 1662: 1659: 1657: 1654: 1652: 1649: 1647: 1644: 1642: 1639: 1637: 1634: 1632: 1629: 1627: 1624: 1622: 1619: 1617: 1614: 1612: 1609: 1607: 1604: 1602: 1599: 1598: 1596: 1594: 1590: 1580: 1577: 1575: 1574:Systemic risk 1572: 1570: 1567: 1565: 1562: 1561: 1559: 1555: 1549: 1546: 1544: 1541: 1539: 1536: 1534: 1531: 1529: 1526: 1524: 1523:Business risk 1521: 1519: 1516: 1515: 1513: 1511: 1507: 1500: 1496: 1492: 1489: 1487: 1484: 1482: 1479: 1477: 1474: 1472: 1469: 1467: 1464: 1462: 1459: 1457: 1454: 1451: 1447: 1443: 1439: 1435: 1431: 1428: 1427: 1425: 1423: 1419: 1413: 1410: 1408: 1405: 1403: 1400: 1398: 1395: 1393: 1390: 1388: 1385: 1383: 1380: 1379: 1377: 1375: 1371: 1368: 1364: 1360: 1356: 1349: 1344: 1342: 1337: 1335: 1330: 1329: 1326: 1320: 1317: 1315: 1312: 1310: 1307: 1305: 1301: 1298: 1297: 1293: 1284: 1278: 1274: 1267: 1264: 1257: 1255: 1227: 1224: 1217: 1214: 1209: 1205: 1198: 1195: 1189: 1184: 1179: 1175: 1152: 1148: 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1695: 1676:Sharpe ratio 1538:Country risk 1499:Deposit risk 1397:Default risk 1272: 1266: 667: 656: 635: 454:optimization 365: 105: 88: 76: 49: 28: 24: 18: 1965:Toxic asset 1925:Speculation 1858:social work 1843:engineering 1671:Risk parity 1656:Omega ratio 1569:Profit risk 1456:Equity risk 1434:Volume risk 1422:Market risk 1374:Credit risk 647:Index funds 74:decisions. 52:index funds 29:active risk 2003:Categories 1548:Legal risk 1528:Model risk 1442:Shape risk 1438:Basis risk 1366:Categories 1258:References 820:index and 85:Definition 1895:Risk pool 1808:Financial 1235:otherwise 1121:≥ 1098:ℓ 1075:∈ 1038:≤ 1025:≤ 1006:ℓ 993:≤ 963:∑ 945:≤ 914:ω 828:Σ 818:benchmark 794:− 758:− 749:Σ 726:− 708:ω 681:ω 598:≤ 579:ω 575:≤ 559:− 550:Σ 527:− 495:− 480:μ 427:− 384:− 336:− 320:Σ 297:− 251:− 227:− 201:− 157:− 141:⁡ 130:ω 1818:analysis 1753:Bad debt 1631:Drawdown 1593:Modeling 888:problem: 641:Examples 102:Formulas 1833:betting 1823:analyst 1813:adviser 1466:FX risk 1304:YouTube 840:is the 657:inverse 21:finance 1875:Hazard 1626:Copula 1493:(e.g. 1432:(e.g. 1279:  1140:where 783:where 699:to be: 366:where 68:factor 1880:Hedge 1838:crime 1828:asset 1661:RAROC 1557:Other 670:index 1890:Risk 1853:risk 1357:and 1277:ISBN 1215:> 928:s.t. 516:s.t. 92:beta 64:risk 1848:law 1793:ESG 901:min 469:max 138:Var 27:or 19:In 2005:: 1719:, 1715:, 1711:, 1707:, 1497:, 1448:, 1444:, 1440:, 1436:, 1302:- 23:, 1723:) 1692:) 1688:( 1501:) 1452:) 1347:e 1340:t 1333:v 1285:. 1228:, 1225:0 1218:0 1210:j 1206:w 1199:, 1196:1 1190:{ 1185:= 1180:j 1176:y 1153:j 1149:y 1124:0 1116:j 1112:u 1107:, 1102:j 1093:, 1090:} 1087:1 1084:, 1081:0 1078:{ 1070:j 1066:y 1061:, 1056:j 1052:y 1046:j 1042:u 1033:j 1029:w 1020:j 1016:y 1010:j 996:K 988:j 984:y 978:N 973:1 970:= 967:j 958:, 953:j 949:y 940:j 936:w 918:2 905:w 872:K 852:N 802:b 798:w 791:w 771:) 766:b 762:w 755:w 752:( 744:T 740:) 734:b 730:w 723:w 720:( 717:= 712:2 685:2 617:d 614:= 611:x 608:C 604:, 601:b 595:x 592:A 588:, 583:2 572:) 567:b 563:w 556:w 553:( 545:T 541:) 535:b 531:w 524:w 521:( 511:, 508:) 503:b 499:w 492:w 489:( 484:T 473:w 460:: 440:) 435:b 431:w 422:p 418:w 414:( 392:b 388:r 379:p 375:r 349:) 344:b 340:w 331:p 327:w 323:( 315:T 311:) 305:b 301:w 292:p 288:w 284:( 279:= 272:2 268:) 264:] 259:b 255:r 246:p 242:r 238:[ 234:E 230:( 224:] 219:2 215:) 209:b 205:r 196:p 192:r 188:( 185:[ 181:E 175:= 170:) 165:b 161:r 152:p 148:r 144:( 133:= 127:= 124:E 121:T

Index

finance
investment portfolio
active management
portfolio manager
standard deviation
index funds
actively manage
active returns
risk
factor
market timing
information ratio
beta
multi-factor fixed income models
standard deviation
optimization
second-order cone programming
Index funds
Inverse exchange-traded funds
index
benchmark
covariance matrix
mixed-integer quadratic programming (MIQP)
ISBN
978-0521861700
Tracking Error
YouTube
Tracking error: A hidden cost of passive investing
Tracking error
What is the Tracking Error?

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