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Talk:Dense subgraph

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81: 71: 53: 22: 444:, the central vertex has high degree, and so the subgraph consisting only of that vertex would seem to have high average degree (if you measure degree in terms of the whole graph, not the subgraph). But it is not a dense subgraph. One possibility would be to replace "a high level of internal connectivity" with "many edges per vertex", or something like that. — 372:
Now, being 4-regular, it has a subgraph density of 2, and any proper subgraph has a lower density. But if we wanted to maximise internal connectivity, we would have chosen one of the "sides", e.g.
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The example does not show the densest subgraph ... the induced graph $ G'=(V' = \{b,c,d,e,f,g,h\}, \choose{V'}{2} \cap E(G))$ has density $ d_{G'} = \frac{10}{7} = 1.428571 : -->
440:"Connectivity" here was intended in a less formal sense than the one you are using. But your suggested replacement, "average degree", would also be confusing. For instance, in a 414: 190:
The first sentence of the article currently reads: "In graph theory and computer science, a dense subgraph is a subgraph with a high level of internal connectivity."
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Consider the following example of a 4-regular graph on 10 vertices that contains a 2-edge cut:
70: 52: 375: 169:? graph density is |E| / choose(|V|, 2), yet subgraph density here is defined as |E| / |V|. 466: 423: 288: 346: 320: 461:
The suggestion of "many edges per vertex" (or something like that) sounds much better.
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But the notion of connectivity here confused me when first reading it.
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I absolutely see, now, why my suggested replacement was also confusing.
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be the edges of the 2-edge cut. Insert 3 parallel edges between
15: 378: 349: 323: 291: 271: 251: 228: 205: 98:, a collaborative effort to improve the coverage of 408: 361: 335: 309: 277: 257: 237: 214: 132:This article has not yet received a rating on the 165:should subgraph density be defined similarly to 317:, and connect these new vertices by a triangle 8: 19: 427: 47: 377: 348: 322: 290: 270: 250: 227: 204: 416:, which I believe is 3-edge connected. 49: 285:, subdivide them introducing vertices 520:Unknown-priority mathematics articles 7: 92:This article is within the scope of 38:It is of interest to the following 14: 112:Knowledge:WikiProject Mathematics 515:Start-Class mathematics articles 115:Template:WikiProject Mathematics 79: 69: 51: 20: 1: 471:14:49, 31 December 2022 (UTC) 454:07:58, 31 December 2022 (UTC) 434:07:31, 31 December 2022 (UTC) 426:) 08:21, Dec 31, 2022 (ECT) 106:and see a list of open tasks. 500:13:07, 12 August 2014 (UTC) 536: 409:{\displaystyle a,b,c,d,e} 186:First sentence confusing? 181:20:10, 12 July 2013 (UTC) 131: 64: 46: 134:project's priority scale 95:WikiProject Mathematics 410: 363: 337: 311: 279: 259: 239: 216: 28:This article is rated 484:1.4 = \frac{7}{5}$ 411: 364: 338: 312: 310:{\displaystyle c,d,e} 280: 260: 240: 217: 376: 347: 321: 289: 269: 249: 226: 203: 118:mathematics articles 442:Star (graph theory) 362:{\displaystyle x,y} 343:. Similarly on the 336:{\displaystyle cde} 406: 359: 333: 307: 275: 255: 238:{\displaystyle by} 235: 215:{\displaystyle ax} 212: 87:Mathematics portal 34:content assessment 490:comment added by 479:Example incorrect 436: 278:{\displaystyle b} 258:{\displaystyle a} 148: 147: 144: 143: 140: 139: 527: 502: 415: 413: 412: 407: 368: 366: 365: 360: 342: 340: 339: 334: 316: 314: 313: 308: 284: 282: 281: 276: 264: 262: 261: 256: 244: 242: 241: 236: 221: 219: 218: 213: 162: 161: 157: 120: 119: 116: 113: 110: 89: 84: 83: 73: 66: 65: 55: 48: 31: 25: 24: 16: 535: 534: 530: 529: 528: 526: 525: 524: 505: 504: 485: 481: 374: 373: 345: 344: 319: 318: 287: 286: 267: 266: 247: 246: 224: 223: 201: 200: 188: 163: 159: 155: 153: 152: 117: 114: 111: 108: 107: 85: 78: 32:on Knowledge's 29: 12: 11: 5: 533: 531: 523: 522: 517: 507: 506: 492:134.34.225.175 480: 477: 476: 475: 474: 473: 459: 446:David Eppstein 432:comment added 405: 402: 399: 396: 393: 390: 387: 384: 381: 358: 355: 352: 332: 329: 326: 306: 303: 300: 297: 294: 274: 254: 234: 231: 211: 208: 187: 184: 151: 149: 146: 145: 142: 141: 138: 137: 130: 124: 123: 121: 104:the discussion 91: 90: 74: 62: 61: 56: 44: 43: 37: 26: 13: 10: 9: 6: 4: 3: 2: 532: 521: 518: 516: 513: 512: 510: 503: 501: 497: 493: 489: 478: 472: 468: 464: 460: 457: 456: 455: 451: 447: 443: 439: 438: 437: 435: 431: 425: 421: 417: 403: 400: 397: 394: 391: 388: 385: 382: 379: 370: 356: 353: 350: 330: 327: 324: 304: 301: 298: 295: 292: 272: 252: 232: 229: 209: 206: 197: 194: 191: 185: 183: 182: 178: 174: 170: 168: 167:graph density 158: 150: 135: 129: 126: 125: 122: 105: 101: 97: 96: 88: 82: 77: 75: 72: 68: 67: 63: 60: 57: 54: 50: 45: 41: 35: 27: 23: 18: 17: 486:— Preceding 482: 428:— Preceding 418: 371: 198: 195: 192: 189: 171: 164: 93: 40:WikiProjects 109:Mathematics 100:mathematics 59:Mathematics 30:Start-class 509:Categories 488:unsigned 430:undated 369:side. 173:Mmuurr 154:": --> 36:scale. 463:Vuniu 420:Vuniu 496:talk 467:talk 450:talk 424:talk 265:and 222:and 199:Let 177:talk 156:edit 128:??? 511:: 498:) 469:) 452:) 179:) 494:( 465:( 448:( 422:( 404:e 401:, 398:d 395:, 392:c 389:, 386:b 383:, 380:a 357:y 354:, 351:x 331:e 328:d 325:c 305:e 302:, 299:d 296:, 293:c 273:b 253:a 233:y 230:b 210:x 207:a 175:( 160:] 136:. 42::

Index


content assessment
WikiProjects
WikiProject icon
Mathematics
WikiProject icon
icon
Mathematics portal
WikiProject Mathematics
mathematics
the discussion
???
project's priority scale
graph density
Mmuurr
talk
20:10, 12 July 2013 (UTC)
Vuniu
talk
undated
07:31, 31 December 2022 (UTC)
Star (graph theory)
David Eppstein
talk
07:58, 31 December 2022 (UTC)
Vuniu
talk
14:49, 31 December 2022 (UTC)
unsigned
134.34.225.175

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