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Seven-number summary

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252:
depend on the number of samples, this seven-number summary does not, and is somewhat more stable, since its whisker-ends are protected from the usual wild swings in the extreme values of the sample by replacing them with the more steady 2nd and 98th percentiles.
605:
Note that the middle five of the seven numbers can all be obtained by successive partitioning of the ordered data into subsets of equal size. Extending the seven-number summary by continued partitioning produces the
245:, so the plotted values provide a convenient visual check for validity of later tests, simply by scanning to see if the marks for those seven percentiles appear to be equal distances apart on the graph. 260:. The 2nd and 98th percentiles are represented by the ends of the whiskers, and hatch-marks across the whiskers mark the 9th and 91st percentiles. 237:
The two unusual percentiles at either end are used because the locations of all seven values will be approximately equally spaced if the data is
647:
The seven equally spaced percentiles with three digits of precision are 2.15%, 8.87%, 25.0%, 50.0%, 75.0%, 91.13%, and 97.85%.
434:, which for a normal distribution can be scaled to give a reasonably efficient estimate of standard deviation, and the 10% 427:
Note that the middle five of the seven numbers are very nearly the same as for the seven number summary, above.
731: 272: 711: 623: 17: 681: 705: 8: 249: 242: 238: 227: 62: 52: 29: 25: 675: 431: 686:
the seven positions are the maximum and minimum, median, quartiles, and two deciles
594: 498: 416: 320: 725: 671: 268: 39:, adding hatch-marks on the "whiskers" for two of the additional numbers. 581: 513: 454: 701: 481: 450: 435: 303: 83: 76: 48: 35:
As with the five-number summary, it can be represented by a modified
563: 549: 526: 458: 439: 385: 371: 348: 280: 257: 231: 223: 215: 172: 154: 130: 36: 628: 543: 403: 365: 335: 276: 219: 150: 275:, called a "seven-figure summary", including the extremes, 438:, which when compared to the median gives an idea of the 453:
used a seven-number summary consisting of the extremes,
430:
The addition of the deciles allow one to compute the
723: 263: 445: 256:The values can be represented using a modified 248:Notice that whereas the extreme values of the 666: 664: 230:and are the standard values for the box in a 696: 694: 661: 226:– are the usual statistics from the 51:are (approximately) evenly spaced under a 691: 32:. There are three similar, common forms. 597:(nominal: lowest hundredth percentile) 419:(nominal: lowest hundredth percentile) 42: 724: 670: 501:(nominal: highest zero-th percentile) 323:(nominal: highest zero-th percentile) 700: 214:The middle three values – the 13: 14: 743: 677:Elementary Manual of Statistics 241:Some statistical tests require 641: 293:Bowley’s seven summary figures 192:upper whisker crosshatch mark 116:lower whisker crosshatch mark 1: 654: 471:Tukey’s seven summary figures 264:Bowley’s seven-figure summary 28:, and is an extension of the 634: 446:Tukey’s seven-number summary 7: 617: 10: 748: 283:, along with the median. 81: More precise  707:Exploratory Data Analysis 273:non-parametric statistics 243:normally distributed data 102:lower whisker bottom end 74: Approximate  24:is a collection of seven 680:(3rd ed.). p.  464:The seven numbers are: 624:Three-point estimation 286:Thus the numbers are: 206:upper whisker top end 18:descriptive statistics 612:eleven-number summary 65:seven summary numbers 239:normally distributed 53:normally distributed 43:Seven-number summary 22:seven-number summary 608:nine-number summary 546:, middle value, or 473: 368:, middle value, or 295: 250:five-number summary 228:five-number summary 153:, middle value, or 67: 63:Normal distribution 30:five-number summary 732:Summary statistics 487:Alternate name(s) 469: 461:, and the median. 309:Alternate name(s) 291: 88:Alternate name(s) 60: 26:summary statistics 601: 600: 432:interdecile range 423: 422: 210: 209: 739: 716: 715: 698: 689: 688: 668: 648: 645: 474: 472: 468: 296: 294: 290: 68: 66: 59: 747: 746: 742: 741: 740: 738: 737: 736: 722: 721: 720: 719: 699: 692: 669: 662: 657: 652: 651: 646: 642: 637: 620: 470: 448: 292: 266: 156:second quartile 82: 75: 61: 45: 12: 11: 5: 745: 735: 734: 718: 717: 690: 659: 658: 656: 653: 650: 649: 639: 638: 636: 633: 632: 631: 626: 619: 616: 603: 602: 599: 598: 595:sample maximum 592: 589: 585: 584: 578: 575: 571: 570: 568:third quartile 564:upper quartile 561: 558: 554: 553: 541: 538: 534: 533: 531:first quartile 527:lower quartile 524: 521: 517: 516: 510: 507: 503: 502: 499:sample minimum 496: 493: 489: 488: 485: 478: 447: 444: 442:in the tails. 425: 424: 421: 420: 417:sample maximum 414: 411: 407: 406: 400: 397: 393: 392: 390:third quartile 386:upper quartile 383: 380: 376: 375: 363: 360: 356: 355: 353:first quartile 349:lower quartile 346: 343: 339: 338: 332: 329: 325: 324: 321:sample minimum 318: 315: 311: 310: 307: 300: 271:used a set of 265: 262: 224:upper quartile 216:lower quartile 212: 211: 208: 207: 204: 201: 198: 194: 193: 190: 187: 184: 180: 179: 177:third quartile 173:upper quartile 170: 167: 164: 160: 159: 148: 145: 142: 138: 137: 135:first quartile 131:lower quartile 128: 125: 122: 118: 117: 114: 111: 108: 104: 103: 100: 97: 94: 90: 89: 86: 79: 72: 47:The following 44: 41: 9: 6: 4: 3: 2: 744: 733: 730: 729: 727: 713: 709: 708: 703: 697: 695: 687: 683: 679: 678: 673: 667: 665: 660: 644: 640: 630: 627: 625: 622: 621: 615: 614:, and so on. 613: 609: 596: 593: 590: 587: 586: 583: 579: 576: 573: 572: 569: 565: 562: 559: 556: 555: 552: 551: 545: 542: 539: 536: 535: 532: 528: 525: 522: 519: 518: 515: 511: 508: 505: 504: 500: 497: 494: 491: 490: 486: 483: 479: 476: 475: 467: 466: 465: 462: 460: 456: 452: 443: 441: 437: 433: 428: 418: 415: 412: 409: 408: 405: 401: 398: 395: 394: 391: 387: 384: 381: 378: 377: 374: 373: 367: 364: 361: 358: 357: 354: 350: 347: 344: 341: 340: 337: 333: 330: 327: 326: 322: 319: 316: 313: 312: 308: 305: 301: 298: 297: 289: 288: 287: 284: 282: 278: 274: 270: 269:Arthur Bowley 261: 259: 254: 251: 246: 244: 240: 235: 233: 229: 225: 221: 217: 205: 202: 199: 196: 195: 191: 188: 185: 182: 181: 178: 174: 171: 168: 165: 162: 161: 158: 157: 152: 149: 146: 143: 140: 139: 136: 132: 129: 126: 123: 120: 119: 115: 112: 109: 106: 105: 101: 98: 95: 92: 91: 87: 85: 80: 78: 73: 70: 69: 64: 58: 57: 56: 54: 50: 40: 38: 33: 31: 27: 23: 19: 706: 685: 676: 643: 611: 607: 604: 567: 547: 530: 463: 449: 429: 426: 389: 369: 352: 285: 267: 255: 247: 236: 213: 176: 155: 134: 46: 34: 21: 15: 113: 8.87% 99: 2.15% 49:percentiles 710:. p.  672:Bowley, A. 655:References 482:Percentile 451:John Tukey 436:midsummary 304:Percentile 84:percentile 77:percentile 55:variable: 702:Tukey, J. 635:Footnotes 459:quartiles 281:quartiles 110: 9th 96: 2nd 726:Category 704:(1977). 674:(1920). 618:See also 550:quartile 440:skewness 372:quartile 258:box plot 232:box plot 37:box plot 629:Stanine 548:second 484:  480:  455:octiles 370:second 306:  302:  277:deciles 610:, the 582:octile 544:median 514:octile 512:first 404:decile 366:median 336:decile 334:first 279:, and 222:, and 220:median 203:97.85% 189:91.13% 169:75.00% 151:median 147:50.00% 127:25.00% 20:, the 580:last 577:87.5% 560:75.0% 540:50.0% 523:25.0% 509:12.5% 402:last 591:100% 413:100% 200:98th 186:91st 166:75th 144:50th 124:25th 566:or 529:or 477:Nr. 399:90% 388:or 382:75% 362:50% 351:or 345:25% 331:10% 299:Nr. 175:or 133:or 71:Nr. 16:In 728:: 712:53 693:^ 684:. 682:62 663:^ 588:#7 574:#6 557:#5 537:#4 520:#3 506:#2 495:0% 492:#1 457:, 410:#7 396:#6 379:#5 359:#4 342:#3 328:#2 317:0% 314:#1 234:. 218:, 197:#7 183:#6 163:#5 141:#4 121:#3 107:#2 93:#1 714:.

Index

descriptive statistics
summary statistics
five-number summary
box plot
percentiles
normally distributed
Normal distribution
percentile
percentile
lower quartile
median
second quartile
upper quartile
lower quartile
median
upper quartile
five-number summary
box plot
normally distributed
normally distributed data
five-number summary
box plot
Arthur Bowley
non-parametric statistics
deciles
quartiles
Percentile
sample minimum
decile
lower quartile

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