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Step detection

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These algorithms start with the assumption that there are no steps and introduce possible candidate steps one at a time, testing each candidate to find the one that minimizes some criteria (such as the least-squares fit of the estimated, underlying piecewise constant signal). An example is the
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By considering a small "window" of the signal, these algorithms look for evidence of a step occurring within the window. The window "slides" across the time series, one time step at a time. The evidence for a step is tested by statistical procedures, for example, by use of the two-sample
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All the algorithms mentioned above have certain advantages and disadvantages in particular circumstances, yet, a surprisingly large number of these step detection algorithms are special cases of a more general algorithm. This algorithm involves the minimization of a global functional:
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Many algorithms explicitly fit 0-degree splines to the noisy signal in order to detect steps (including stepwise jump placement methods), but there are other popular algorithms that can also be seen to be spline fitting methods after some transformation, for example
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Bottom-up algorithms take the "opposite" approach to top-down methods, first assuming that there is a step in between every sample in the digital signal, and then successively merging steps based on some criteria tested for every candidate merge.
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In: Large-Scale Disturbances (Regime Shifts) and Recovery in Aquatic Ecosystems: Challenges for Management Toward Sustainability, V. Velikova and N. Chipev (Eds.), UNESCO-ROSTE/BAS Workshop on Regime Shifts, 14–16 June 2005, Varna, Bulgaria,
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Mumford, D., & Shah, J. (1989). Optimal approximations by piecewise smooth functions and associated variational problems. Communications on pure and applied mathematics, 42(5), 577-685.
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Sowa, Y.; Rowe, A. D.; Leake, M. C.; Yakushi, T.; Homma, M.; Ishijima, A.; Berry, R. M. (2005). "Direct observation of steps in rotation of the bacterial flagellar motor".
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algorithms are applied to the data potentially long after it has been received. Most offline algorithms for step detection in digital data can be categorised as
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Kerssemakers, J.W.J.; Munteanu, E.L.; Laan, L.; Noetzel, T.L.; Janson, M.E.; Dogterom, M. (2006). "Assembly dynamics of microtubules at molecular resolution".
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Global algorithms consider the entire signal in one go, and attempt to find the steps in the signal by some kind of optimization procedure. Algorithms include
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with a few unique levels. Many algorithms for step detection are therefore best understood as either 0-degree spline fitting, or level set recovery, methods.
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are appropriate. These techniques are best understood as methods for finding a level set description of the underlying piecewise constant signal.
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Because the aim of step detection is to find a series of instantaneous jumps in the mean of a signal, the wanted, underlying, mean signal is
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are also often used (a popular approach in the biophysics community). When there are only a few unique values of the mean, then
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A classical variational method for step detection is the Potts model. It is given by the non-convex optimization problem
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Gill, D. (1970). "Application of a statistical zonation method to reservoir evaluation and digitized log analysis".
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Mrazek, P.; Weickert, J.; Bruhn, A. (2006). "On robust estimation and smoothing with spatial and tonal kernels".
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is applied to the signal. Filters such as these attempt to remove the noise whilst preserving the abrupt steps.
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Chan, D.; T. Chan (2003). "Edge-preserving and scale-dependent properties of total variation regularization".
2199:"Generalized methods and solvers for noise removal from piecewise constant signals: Part I. Background theory" 1914:
Snijders, A.M.; et al. (2001). "Assembly of microarrays for genome-wide measurement of DNA copy number".
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or change point detection. Often, the step is small and the time series is corrupted by some kind of
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specifying a group of algorithms that attempt to greedily fit 0-degree splines to the signal. Here,
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algorithm, when using an adaptive step size Euler integrator initialized with the input signal 
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algorithm, first studied in geophysical problems, that has found recent uses in modern biophysics.
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The step detection problem occurs in multiple scientific and engineering contexts, for example in
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PWCTools: Flexible Matlab and Python software for step detection by piecewise constant denoising
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approaches to step detection generally do not use classical smoothing techniques such as the
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or signal. It is usually considered as a special case of the statistical method known as
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Friedrich; et al. (2008). "Complexity penalized M-estimation: fast computation".
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Mallat, S.; Hwang, W.L. (1992). "Singularity detection and processing with wavelets".
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E.S. Page (1955). "A test for a change in a parameter occurring at an unknown point".
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is piecewise constant the steps are given by the non-zero locations of the gradient
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Pottslab: Matlab toolbox for piecewise constant estimation based on the Potts model
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When there are only a few unique values of the mean, clustering techniques such as
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there are fast algorithms which give an exact solution of the Potts problem in
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Rodionov, S.N., 2005a: A brief overview of the regime shift detection methods.
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When the step detection must be performed as and when the data arrives, then
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as recorded in time-position traces). For 2D signals, the related problem of
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Winkler, G.; Liebscher, V. (2002). "Smoothers for discontinuous signals".
117: 43:, and (d) red pixel intensity from a single scan line of a digital image. 2078: 1978: 16: 239: 2131: 1665:. The parameter γ > 0 controls the tradeoff between regularity and 2437: 286:. Instead, most algorithms are explicitly nonlinear or time-varying. 266:
Linear versus nonlinear signal processing methods for step detection
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Examples of signals that may contain steps corrupted by noise. (a)
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Because steps and (independent) noise have theoretically infinite
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is the signal output from the algorithm. The goal is to minimize
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is the spatial kernel support. Yet another special case is:
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determines the particular algorithm. For example, choosing:
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Generalized step detection by piecewise constant denoising
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being the most directly related method), in exploration
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American Association of Petroleum Geologists Bulletin
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are usually used, and it becomes a special case of
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Detection of Abrupt Changes: Theory and Application
2416: 1806: 1770: 1744: 1718: 1688: 1653: 1545: 1459: 1327: 1292: 1252: 1078: 1043: 884: 789: 750: 587: 511: 2365:Journal of Computational and Graphical Statistics 1381: 813: 1293:{\displaystyle \scriptstyle \left|x\right|^{0}} 2192: 2190: 290:Step detection and piecewise constant signals 8: 1573: 1560: 1540: 1502: 1487: 1477: 1443: 1430: 1418: 1408: 552:is the discrete-time input signal of length 1901:10.1306/5d25ca35-16c1-11d7-8645000102c1865d 1553:penalizes the number of jumps and the term 1339:: they can be minimized using methods from 2397:A. Weinmann, M. Storath, L. Demaret. "The 2052: 2050: 2048: 2010:Image analysis and mathematical morphology 1882: 1880: 1878: 1876: 2408: 2402: 2299: 2297: 2295: 2232: 2170: 2145:McKinney, S. A.; Joo, C.; Ha, T. (2006). 2121: 1864: 1795: 1783: 1757: 1731: 1710: 1701: 1680: 1674: 1645: 1640: 1633: 1620: 1611: 1605: 1594: 1581: 1576: 1558: 1528: 1515: 1490: 1475: 1451: 1446: 1421: 1397: 1393: 1392: 1384: 1365: 1359: 1318: 1283: 1268: 1220: 1209: 1196: 1150: 1139: 1126: 1106: 1098: 1063: 1027: 1013: 987: 981: 976: 969: 956: 947: 923: 915: 865: 854: 841: 821: 805: 782: 773:is false, and one otherwise, obtains the 713: 700: 655: 644: 631: 611: 603: 578: 488: 475: 462: 449: 436: 423: 407: 396: 386: 375: 354: 326:Step detection as 0-degree spline fitting 2306:Geometric properties for incomplete data 1079:{\displaystyle \scriptstyle \beta >0} 777:algorithm with regularization parameter 160:. Such algorithms include the classical 2110:IEEE Transactions on Information Theory 2023:Basseville, M.; I.V. Nikiforov (1993). 1835: 569:with respect to the output signal  250:. Where the steps can be modelled as a 1313:) defined by the particular choice of 1328:{\displaystyle \scriptstyle \Lambda } 1307:Many of the functionals in equation ( 588:{\displaystyle \scriptstyle \Lambda } 36:, (c) rotation speed against time of 7: 1347:Step detection using the Potts model 346: 310:Step detection as level set recovery 2473:Feature detection (computer vision) 2330:Journal of Nonparametric Statistics 2012:. London; New York: Academic Press. 1304: = 0, and one otherwise. 1086:is the tonal kernel parameter, and 164:method applied to changes in mean. 108:(where the problem is to segment a 2204:Proceedings of the Royal Society A 2197:Little, M.A.; Jones, N.S. (2011). 1703: 1499: 1480: 1411: 1321: 1100: 917: 807: 605: 581: 413: 132:(detecting state transitions in a 14: 769:) = 0 if the condition 140:has been studied intensively for 548: = 1, ....,  1801: 1788: 1641: 1612: 1247: 1229: 1177: 1159: 1038: 1028: 1014: 1010: 995: 977: 948: 938: 745: 727: 682: 664: 506: 416: 365: 359: 1: 2468:Statistical signal processing 2308:. Berlin, Germany: Springer. 1719:{\displaystyle \nabla u^{*}} 2163:10.1529/biophysj.106.082487 1309: 573:. The form of the function 120:(the problem of separating 98:statistical process control 2489: 2278:10.1088/0266-5611/19/6/059 1661:measures fidelity to data 1857:10.1093/biomet/42.3-4.523 775:total variation denoising 333:total variation denoising 244:total variation denoising 2377:10.1198/106186008x285591 1824:Time-series segmentation 1807:{\displaystyle O(N^{2})} 302:with a few knots, or as 246:which uses methods from 790:{\displaystyle \gamma } 198:stepwise jump placement 2418: 2342:10.1080/10485250211388 2225:10.1098/rspa.2010.0671 1808: 1772: 1746: 1720: 1690: 1669:. Since the minimizer 1655: 1610: 1547: 1461: 1329: 1300:is defined as zero if 1294: 1254: 1080: 1045: 886: 791: 752: 589: 513: 412: 391: 274:and so overlap in the 44: 22:DNA copy-number ratios 2419: 2417:{\displaystyle L^{1}} 1809: 1773: 1747: 1721: 1691: 1689:{\displaystyle u^{*}} 1656: 1590: 1548: 1462: 1330: 1295: 1255: 1081: 1046: 887: 792: 753: 590: 514: 392: 371: 19: 2401: 2008:Serra, J.P. (1982). 1782: 1756: 1730: 1700: 1673: 1557: 1474: 1358: 1317: 1267: 1097: 1062: 914: 804: 781: 602: 577: 353: 256:Hidden Markov Models 2270:2003InvPr..19S.165S 2217:2011RSPSA.467.3088L 2211:(2135): 3088–3114. 2151:Biophysical Journal 2079:10.1038/nature04928 2071:2006Natur.442..709K 1979:10.1038/nature04003 1971:2005Natur.437..916S 1771:{\displaystyle p=1} 1745:{\displaystyle p=2} 1586: 1456: 1341:convex optimization 248:convex optimization 222:. Alternatively, a 158:sequential analysis 114:stratigraphic zones 2414: 1866:10338.dmlcz/103435 1804: 1768: 1742: 1716: 1686: 1651: 1572: 1543: 1457: 1442: 1404: 1325: 1324: 1290: 1289: 1250: 1076: 1075: 1041: 882: 787: 748: 585: 584: 509: 316:k-means clustering 296:piecewise constant 262:can also be used. 260:k-means clustering 124:data into similar 45: 2463:Nonlinear filters 2132:10.1109/18.119727 2065:(7103): 709–712. 1965:(7060): 916–919. 1380: 1114: 1002: 829: 619: 533: 532: 280:signal processing 154:online algorithms 134:molecular machine 128:regimes), and in 53:signal processing 32:intensity from a 2480: 2458:Change detection 2425: 2423: 2421: 2420: 2415: 2413: 2412: 2395: 2389: 2388: 2360: 2354: 2353: 2336:(1–2): 203–222. 2325: 2319: 2316: 2310: 2309: 2301: 2290: 2289: 2264:(6): S165–S187. 2258:Inverse Problems 2253: 2247: 2246: 2236: 2194: 2185: 2184: 2174: 2157:(5): 1941–1951. 2142: 2136: 2135: 2125: 2105: 2099: 2098: 2054: 2043: 2035: 2029: 2028: 2027:. Prentice Hall. 2020: 2014: 2013: 2005: 1999: 1998: 1954: 1948: 1947: 1911: 1905: 1904: 1884: 1871: 1870: 1868: 1851:(3–4): 523–527. 1840: 1813: 1811: 1810: 1805: 1800: 1799: 1777: 1775: 1774: 1769: 1751: 1749: 1748: 1743: 1725: 1723: 1722: 1717: 1715: 1714: 1695: 1693: 1692: 1687: 1685: 1684: 1660: 1658: 1657: 1652: 1650: 1649: 1644: 1638: 1637: 1625: 1624: 1615: 1609: 1604: 1585: 1580: 1552: 1550: 1549: 1544: 1539: 1538: 1520: 1519: 1495: 1494: 1466: 1464: 1463: 1458: 1455: 1450: 1426: 1425: 1403: 1402: 1401: 1396: 1370: 1369: 1334: 1332: 1331: 1326: 1299: 1297: 1296: 1291: 1288: 1287: 1282: 1259: 1257: 1256: 1251: 1225: 1224: 1219: 1215: 1214: 1213: 1201: 1200: 1155: 1154: 1149: 1145: 1144: 1143: 1131: 1130: 1115: 1107: 1085: 1083: 1082: 1077: 1056:bilateral filter 1050: 1048: 1047: 1042: 1031: 1017: 1003: 998: 991: 986: 985: 980: 974: 973: 961: 960: 951: 924: 891: 889: 888: 883: 881: 877: 870: 869: 864: 860: 859: 858: 846: 845: 830: 822: 796: 794: 793: 788: 757: 755: 754: 749: 723: 719: 718: 717: 705: 704: 660: 659: 654: 650: 649: 648: 636: 635: 620: 612: 594: 592: 591: 586: 527: 518: 516: 515: 510: 493: 492: 480: 479: 467: 466: 454: 453: 441: 440: 428: 427: 411: 406: 390: 385: 347: 300:0-degree splines 224:nonlinear filter 220:Student's t-test 142:image processing 87:change detection 2488: 2487: 2483: 2482: 2481: 2479: 2478: 2477: 2448: 2447: 2434: 2429: 2428: 2404: 2399: 2398: 2396: 2392: 2362: 2361: 2357: 2327: 2326: 2322: 2317: 2313: 2303: 2302: 2293: 2255: 2254: 2250: 2196: 2195: 2188: 2144: 2143: 2139: 2107: 2106: 2102: 2056: 2055: 2046: 2036: 2032: 2022: 2021: 2017: 2007: 2006: 2002: 1956: 1955: 1951: 1916:Nature Genetics 1913: 1912: 1908: 1886: 1885: 1874: 1842: 1841: 1837: 1832: 1820: 1791: 1780: 1779: 1754: 1753: 1728: 1727: 1706: 1698: 1697: 1676: 1671: 1670: 1639: 1629: 1616: 1555: 1554: 1524: 1511: 1486: 1472: 1471: 1417: 1391: 1361: 1356: 1355: 1349: 1315: 1314: 1272: 1271: 1265: 1264: 1205: 1192: 1191: 1187: 1186: 1135: 1122: 1121: 1117: 1116: 1095: 1094: 1060: 1059: 1054:leading to the 975: 965: 952: 925: 912: 911: 850: 837: 836: 832: 831: 820: 816: 802: 801: 779: 778: 709: 696: 695: 691: 640: 627: 626: 622: 621: 600: 599: 575: 574: 564: 543: 525: 484: 471: 458: 445: 432: 419: 351: 350: 341: 328: 312: 292: 284:low pass filter 268: 236: 215: 206: 193: 150: 112:recording into 69:shift detection 59:(also known as 41:flagellar motor 34:neutron monitor 12: 11: 5: 2486: 2484: 2476: 2475: 2470: 2465: 2460: 2450: 2449: 2446: 2445: 2440: 2433: 2432:External links 2430: 2427: 2426: 2411: 2407: 2390: 2371:(1): 201–224. 2355: 2320: 2311: 2291: 2248: 2186: 2137: 2123:10.1.1.36.5153 2116:(2): 617–643. 2100: 2044: 2030: 2015: 2000: 1949: 1922:(3): 263–264. 1906: 1872: 1834: 1833: 1831: 1828: 1827: 1826: 1819: 1816: 1803: 1798: 1794: 1790: 1787: 1767: 1764: 1761: 1741: 1738: 1735: 1713: 1709: 1705: 1683: 1679: 1648: 1643: 1636: 1632: 1628: 1623: 1619: 1614: 1608: 1603: 1600: 1597: 1593: 1589: 1584: 1579: 1575: 1571: 1568: 1565: 1562: 1542: 1537: 1534: 1531: 1527: 1523: 1518: 1514: 1510: 1507: 1504: 1501: 1498: 1493: 1489: 1485: 1482: 1479: 1468: 1467: 1454: 1449: 1445: 1441: 1438: 1435: 1432: 1429: 1424: 1420: 1416: 1413: 1410: 1407: 1400: 1395: 1390: 1387: 1383: 1379: 1376: 1373: 1368: 1364: 1348: 1345: 1323: 1286: 1281: 1278: 1275: 1261: 1260: 1249: 1246: 1243: 1240: 1237: 1234: 1231: 1228: 1223: 1218: 1212: 1208: 1204: 1199: 1195: 1190: 1185: 1182: 1179: 1176: 1173: 1170: 1167: 1164: 1161: 1158: 1153: 1148: 1142: 1138: 1134: 1129: 1125: 1120: 1113: 1110: 1105: 1102: 1074: 1071: 1068: 1052: 1051: 1040: 1037: 1034: 1030: 1026: 1023: 1020: 1016: 1012: 1009: 1006: 1001: 997: 994: 990: 984: 979: 972: 968: 964: 959: 955: 950: 946: 943: 940: 937: 934: 931: 928: 922: 919: 893: 892: 880: 876: 873: 868: 863: 857: 853: 849: 844: 840: 835: 828: 825: 819: 815: 812: 809: 786: 759: 758: 747: 744: 741: 738: 735: 732: 729: 726: 722: 716: 712: 708: 703: 699: 694: 690: 687: 684: 681: 678: 675: 672: 669: 666: 663: 658: 653: 647: 643: 639: 634: 630: 625: 618: 615: 610: 607: 583: 560: 539: 531: 530: 521: 519: 508: 505: 502: 499: 496: 491: 487: 483: 478: 474: 470: 465: 461: 457: 452: 448: 444: 439: 435: 431: 426: 422: 418: 415: 410: 405: 402: 399: 395: 389: 384: 381: 378: 374: 370: 367: 364: 361: 358: 340: 337: 327: 324: 311: 308: 291: 288: 267: 264: 235: 232: 214: 213:Sliding window 211: 205: 202: 192: 189: 181:sliding window 149: 146: 138:edge detection 78:edge detection 73:jump detection 65:step filtering 61:step smoothing 57:step detection 38:R. Sphaeroides 13: 10: 9: 6: 4: 3: 2: 2485: 2474: 2471: 2469: 2466: 2464: 2461: 2459: 2456: 2455: 2453: 2444: 2441: 2439: 2436: 2435: 2431: 2409: 2405: 2394: 2391: 2386: 2382: 2378: 2374: 2370: 2366: 2359: 2356: 2351: 2347: 2343: 2339: 2335: 2331: 2324: 2321: 2315: 2312: 2307: 2300: 2298: 2296: 2292: 2287: 2283: 2279: 2275: 2271: 2267: 2263: 2259: 2252: 2249: 2244: 2240: 2235: 2230: 2226: 2222: 2218: 2214: 2210: 2206: 2205: 2200: 2193: 2191: 2187: 2182: 2178: 2173: 2168: 2164: 2160: 2156: 2152: 2148: 2141: 2138: 2133: 2129: 2124: 2119: 2115: 2111: 2104: 2101: 2096: 2092: 2088: 2084: 2080: 2076: 2072: 2068: 2064: 2060: 2053: 2051: 2049: 2045: 2040: 2034: 2031: 2026: 2019: 2016: 2011: 2004: 2001: 1996: 1992: 1988: 1984: 1980: 1976: 1972: 1968: 1964: 1960: 1953: 1950: 1945: 1941: 1937: 1933: 1929: 1928:10.1038/ng754 1925: 1921: 1917: 1910: 1907: 1902: 1898: 1894: 1890: 1883: 1881: 1879: 1877: 1873: 1867: 1862: 1858: 1854: 1850: 1846: 1839: 1836: 1829: 1825: 1822: 1821: 1817: 1815: 1796: 1792: 1785: 1765: 1762: 1759: 1739: 1736: 1733: 1711: 1707: 1681: 1677: 1668: 1667:data fidelity 1664: 1646: 1634: 1630: 1626: 1621: 1617: 1606: 1601: 1598: 1595: 1591: 1587: 1582: 1577: 1569: 1566: 1563: 1535: 1532: 1529: 1525: 1521: 1516: 1512: 1508: 1505: 1496: 1491: 1483: 1452: 1447: 1439: 1436: 1433: 1427: 1422: 1414: 1405: 1398: 1388: 1385: 1377: 1374: 1371: 1366: 1362: 1354: 1353: 1352: 1346: 1344: 1342: 1338: 1312: 1311: 1305: 1303: 1284: 1279: 1276: 1273: 1244: 1241: 1238: 1235: 1232: 1226: 1221: 1216: 1210: 1206: 1202: 1197: 1193: 1188: 1183: 1180: 1174: 1171: 1168: 1165: 1162: 1156: 1151: 1146: 1140: 1136: 1132: 1127: 1123: 1118: 1111: 1108: 1103: 1093: 1092: 1091: 1089: 1072: 1069: 1066: 1057: 1035: 1032: 1024: 1021: 1018: 1007: 1004: 999: 992: 988: 982: 970: 966: 962: 957: 953: 944: 941: 935: 932: 929: 926: 920: 910: 909: 908: 906: 902: 898: 895:leads to the 878: 874: 871: 866: 861: 855: 851: 847: 842: 838: 833: 826: 823: 817: 810: 800: 799: 798: 797:. Similarly: 784: 776: 772: 768: 764: 742: 739: 736: 733: 730: 724: 720: 714: 710: 706: 701: 697: 692: 688: 685: 679: 676: 673: 670: 667: 661: 656: 651: 645: 641: 637: 632: 628: 623: 616: 613: 608: 598: 597: 596: 572: 568: 563: 559: 555: 551: 547: 542: 538: 529: 522: 520: 503: 500: 497: 494: 489: 485: 481: 476: 472: 468: 463: 459: 455: 450: 446: 442: 437: 433: 429: 424: 420: 408: 403: 400: 397: 393: 387: 382: 379: 376: 372: 368: 362: 356: 349: 348: 345: 338: 336: 334: 325: 323: 321: 317: 309: 307: 305: 301: 297: 289: 287: 285: 281: 277: 276:Fourier basis 273: 265: 263: 261: 257: 253: 249: 245: 242:methods, and 241: 233: 231: 229: 228:median filter 225: 221: 212: 210: 203: 201: 199: 190: 188: 186: 182: 178: 174: 170: 167:By contrast, 165: 163: 159: 155: 147: 145: 143: 139: 135: 131: 127: 123: 119: 115: 111: 107: 103: 102:control chart 99: 94: 92: 88: 84: 80: 79: 74: 70: 66: 62: 58: 54: 50: 42: 39: 35: 31: 27: 23: 18: 2393: 2368: 2364: 2358: 2333: 2329: 2323: 2314: 2305: 2261: 2257: 2251: 2208: 2202: 2154: 2150: 2140: 2113: 2109: 2103: 2062: 2058: 2033: 2024: 2018: 2009: 2003: 1962: 1958: 1952: 1919: 1915: 1909: 1892: 1888: 1848: 1844: 1838: 1662: 1469: 1350: 1308: 1306: 1301: 1262: 1087: 1053: 904: 900: 894: 770: 766: 762: 760: 570: 566: 561: 557: 553: 549: 545: 540: 536: 534: 523: 342: 329: 313: 293: 269: 252:Markov chain 237: 226:such as the 216: 207: 197: 194: 184: 180: 176: 172: 168: 166: 151: 95: 76: 72: 68: 64: 60: 56: 46: 2039:link to PDF 1895:: 719–729. 126:copy-number 83:time series 2452:Categories 1845:Biometrika 1830:References 897:mean shift 320:mean-shift 304:level sets 148:Algorithms 130:biophysics 122:microarray 106:geophysics 49:statistics 30:cosmic ray 28:data, (b) 26:microarray 2385:117951377 2350:119562495 2118:CiteSeerX 1995:262329024 1712:∗ 1704:∇ 1682:∗ 1627:− 1592:∑ 1574:‖ 1567:− 1561:‖ 1522:≠ 1500:# 1488:‖ 1481:∇ 1478:‖ 1470:The term 1444:‖ 1437:− 1431:‖ 1419:‖ 1412:∇ 1409:‖ 1406:γ 1389:∈ 1378:⁡ 1367:∗ 1322:Λ 1236:− 1203:− 1184:γ 1166:− 1133:− 1101:Λ 1067:β 1033:≤ 1022:− 1005:⋅ 1000:β 963:− 945:β 942:− 936:⁡ 930:− 918:Λ 848:− 808:Λ 785:γ 734:− 707:− 689:γ 671:− 638:− 606:Λ 582:Λ 501:− 482:− 456:− 430:− 414:Λ 394:∑ 373:∑ 272:bandwidth 204:Bottom-up 187:methods. 177:bottom-up 2286:30704800 2243:22003312 2181:16766620 2087:16799566 1987:16208378 1944:19460203 1936:11687795 1818:See also 1058:, where 191:Top-down 173:top-down 118:genetics 110:well-log 2266:Bibcode 2234:3191861 2213:Bibcode 2172:1544307 2095:4359681 2067:Bibcode 1967:Bibcode 903:. Here 254:, then 240:wavelet 169:offline 2383:  2348:  2284:  2241:  2231:  2179:  2169:  2120:  2093:  2085:  2059:Nature 2042:17-24. 1993:  1985:  1959:Nature 1942:  1934:  1726:. For 1337:convex 761:where 556:, and 535:Here, 234:Global 185:global 116:), in 2381:S2CID 2346:S2CID 2282:S2CID 2091:S2CID 1991:S2CID 1940:S2CID 183:, or 162:CUSUM 100:(the 91:noise 24:from 2239:PMID 2177:PMID 2083:PMID 1983:PMID 1932:PMID 1752:and 1335:are 1070:> 544:for 51:and 2373:doi 2338:doi 2274:doi 2229:PMC 2221:doi 2209:467 2167:PMC 2159:doi 2128:doi 2075:doi 2063:442 1975:doi 1963:437 1924:doi 1897:doi 1861:hdl 1853:doi 1814:. 1382:min 1375:arg 933:exp 814:min 318:or 75:or 47:In 2454:: 2379:. 2369:17 2367:. 2344:. 2334:14 2332:. 2294:^ 2280:. 2272:. 2262:19 2260:. 2237:. 2227:. 2219:. 2207:. 2201:. 2189:^ 2175:. 2165:. 2155:91 2153:. 2149:. 2126:. 2114:38 2112:. 2089:. 2081:. 2073:. 2061:. 2047:^ 1989:. 1981:. 1973:. 1961:. 1938:. 1930:. 1920:29 1918:. 1893:54 1891:. 1875:^ 1859:. 1849:42 1847:. 335:. 278:, 179:, 175:, 144:. 71:, 67:, 63:, 55:, 2410:1 2406:L 2387:. 2375:: 2352:. 2340:: 2288:. 2276:: 2268:: 2245:. 2223:: 2215:: 2183:. 2161:: 2134:. 2130:: 2097:. 2077:: 2069:: 1997:. 1977:: 1969:: 1946:. 1926:: 1903:. 1899:: 1869:. 1863:: 1855:: 1802:) 1797:2 1793:N 1789:( 1786:O 1766:1 1763:= 1760:p 1740:2 1737:= 1734:p 1708:u 1678:u 1663:x 1647:p 1642:| 1635:i 1631:x 1622:i 1618:u 1613:| 1607:N 1602:1 1599:= 1596:i 1588:= 1583:p 1578:p 1570:x 1564:u 1541:} 1536:1 1533:+ 1530:i 1526:u 1517:i 1513:u 1509:: 1506:i 1503:{ 1497:= 1492:0 1484:u 1453:p 1448:p 1440:x 1434:u 1428:+ 1423:0 1415:u 1399:N 1394:R 1386:u 1372:= 1363:u 1310:1 1302:x 1285:0 1280:| 1277:x 1274:| 1248:) 1245:1 1242:= 1239:j 1233:i 1230:( 1227:I 1222:0 1217:| 1211:j 1207:m 1198:i 1194:m 1189:| 1181:+ 1178:) 1175:0 1172:= 1169:j 1163:i 1160:( 1157:I 1152:2 1147:| 1141:j 1137:m 1128:i 1124:x 1119:| 1112:2 1109:1 1104:= 1088:W 1073:0 1039:) 1036:W 1029:| 1025:j 1019:i 1015:| 1011:( 1008:I 996:) 993:2 989:/ 983:2 978:| 971:j 967:m 958:i 954:m 949:| 939:( 927:1 921:= 905:W 901:x 879:} 875:W 872:, 867:2 862:| 856:j 852:m 843:i 839:m 834:| 827:2 824:1 818:{ 811:= 771:S 767:S 765:( 763:I 746:) 743:1 740:= 737:j 731:i 728:( 725:I 721:| 715:j 711:m 702:i 698:m 693:| 686:+ 683:) 680:0 677:= 674:j 668:i 665:( 662:I 657:2 652:| 646:j 642:m 633:i 629:x 624:| 617:2 614:1 609:= 571:m 567:H 562:i 558:m 554:N 550:N 546:i 541:i 537:x 528:) 526:1 524:( 507:) 504:j 498:i 495:, 490:j 486:x 477:i 473:x 469:, 464:j 460:m 451:i 447:m 443:, 438:j 434:m 425:i 421:x 417:( 409:N 404:1 401:= 398:j 388:N 383:1 380:= 377:i 369:= 366:] 363:m 360:[ 357:H

Index


DNA copy-number ratios
microarray
cosmic ray
neutron monitor
R. Sphaeroides
flagellar motor
statistics
signal processing
edge detection
time series
change detection
noise
statistical process control
control chart
geophysics
well-log
stratigraphic zones
genetics
microarray
copy-number
biophysics
molecular machine
edge detection
image processing
online algorithms
sequential analysis
CUSUM
Student's t-test
nonlinear filter

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