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Talk:Tight span

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Right, that's why I moved the part about finiteness into the formal definitions section, and left the introductory sections talking about metric spaces more generally. I am not certain whether the definition here is correct for infinite spaces, whether perhaps the condition on existence of y s.t.
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Yes, that's one of the reasons the connection to orthogonal hull is hard to generalize to higher dimensions. I suppose I should say more about how two-dimensional L1 and Linf are related somewhere in that example.
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Develin & Sturmfels (2004) provide an alternative definition of the tight span of a finite metric space, as the tropical convex hull of the vectors of distances from each point to each other point in the
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f(x)+f(y)=d(x,y) should be replaced by inf f(x)+f(y)-d(x,y)=0, or whether something else is required in the infinite case, so I thought it best to stick to material I was more certain I understood. —
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article. Rather than expunging the error, it's reasonable to show that doing mathematics (or any other science) is an ongoing process, subject to correction when we err.
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The tight span is defined for all metric spaces, not just finite metric spaces, although the applications that I have seen all seem to be for finite metric spaces.
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Holsztyński, Włodzimierz (1968). "Linearisation od isometric embeddings of Banach Spaces. Metric Envelopes.". Bull. Acad. Polon. Sci. 16: 189-193.
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Besides the k-server problem, what other published applications to online algorithms do you know of? I didn't find any when I was looking.
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I don't know of any, but I think that line is left over from Oravec's earlier version, so you could try asking him...—
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always contains Isbell’s injective hull of the metric, but in general these two polyhedral spaces are not equal.
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Later: I found the right definition in Dress et al (it is the inf version) and added it as a footnote. —
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I see. For example, the tight span of the rationals is the reals, and you really need to say "inf."
428:, but may be larger. I've amended the article to show this mis-step and its correction, citing the 352: 240: 215: 170: 159: 324:
isometric embeddings of Banach Spaces. Metric Envelopes.". Bull. Acad. Polon. Sci. 16: 189-193.
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to their paper seems to retract the theorem that the tropical convex hull is the tight span.
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is a symmetric matrix which represents a finite metric, then the tropical polytope
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Wow, you guys developed this article nicely in a short period of time. Congrats.
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I believe that in the T-theory literature, the tight span of
112: 83: 63: 28:This article has not yet been rated on Knowledge's 125: 98: 69: 320:Holsztyński, Włodzimierz (1968). "Linearisation 8: 399:Indeed it does! It says specifically that: 21: 19: 117: 111: 82: 62: 257:I fixed the ambiguity of the statement. 7: 14: 225:Applications to Online Algorithms 20: 93: 87: 1: 394:22:58, 30 November 2012 (UTC) 298:21:50, 11 November 2006 (UTC) 284:20:10, 10 November 2006 (UTC) 262:22:09, 11 November 2006 (UTC) 253:21:50, 11 November 2006 (UTC) 244:16:07, 10 November 2006 (UTC) 234:10:04, 10 November 2006 (UTC) 219:16:07, 10 November 2006 (UTC) 208:10:04, 10 November 2006 (UTC) 187:10:04, 10 November 2006 (UTC) 174:22:43, 9 November 2006 (UTC) 163:19:33, 9 November 2006 (UTC) 152:19:05, 9 November 2006 (UTC) 138:20:27, 8 November 2006 (UTC) 48:09:58, 8 November 2006 (UTC) 473: 442:13:13, 30 March 2017 (UTC) 361:05:26, 2 March 2008 (UTC) 344:02:44, 2 March 2008 (UTC) 199:R is injective with the L 371:In the article it says 417: 127: 100: 71: 43:John Isbell, in 1964. 402: 351:I imagine so. Done. — 203:metric but R is not. 128: 126:{\displaystyle T_{X}} 101: 72: 424:always contains the 422:tropical convex hull 110: 99:{\displaystyle T(X)} 81: 61: 457:Unassessed articles 77:is normally called 275:Great Contribution 123: 96: 67: 39:Who Discovered It? 30:content assessment 367:Tropical approach 346: 330:comment added by 289:Thanks mostly to 70:{\displaystyle X} 36: 35: 464: 332:Nonagonal Spider 325: 316:supposed to be 132: 130: 129: 124: 122: 121: 105: 103: 102: 97: 76: 74: 73: 68: 25: 24: 23: 16: 472: 471: 467: 466: 465: 463: 462: 461: 447: 446: 413: 369: 306: 277: 227: 202: 197: 195:Manhattan Plane 145: 113: 108: 107: 79: 78: 59: 58: 55: 41: 12: 11: 5: 470: 468: 460: 459: 449: 448: 445: 444: 411: 401: 400: 386:SimonWillerton 378: 377: 368: 365: 364: 363: 353:David Eppstein 348: 347: 314: 313: 305: 302: 301: 300: 276: 273: 271: 269: 268: 267: 266: 265: 264: 248:You're right. 241:David Eppstein 226: 223: 222: 221: 216:David Eppstein 200: 196: 193: 192: 191: 190: 189: 177: 176: 171:David Eppstein 166: 165: 160:David Eppstein 144: 141: 120: 116: 95: 92: 89: 86: 66: 54: 51: 40: 37: 34: 33: 26: 13: 10: 9: 6: 4: 3: 2: 469: 458: 455: 454: 452: 443: 439: 435: 431: 427: 423: 420:That is, the 419: 418: 416: 414: 407: 398: 397: 396: 395: 391: 387: 383: 374: 373: 372: 366: 362: 358: 354: 350: 349: 345: 341: 337: 333: 329: 323: 319: 318: 317: 311: 310: 309: 303: 299: 296: 292: 288: 287: 286: 285: 282: 274: 272: 263: 260: 256: 255: 254: 251: 247: 246: 245: 242: 238: 237: 236: 235: 232: 224: 220: 217: 212: 211: 210: 209: 206: 194: 188: 185: 181: 180: 179: 178: 175: 172: 168: 167: 164: 161: 156: 155: 154: 153: 150: 142: 140: 139: 136: 118: 114: 90: 84: 64: 52: 50: 49: 46: 38: 31: 27: 18: 17: 429: 425: 421: 409: 405: 403: 379: 370: 321: 315: 307: 278: 270: 228: 198: 146: 56: 42: 326:—Preceding 426:tight span 304:References 281:Tparameter 295:Vegasprof 250:Vegasprof 231:Vegasprof 205:Vegasprof 184:Vegasprof 149:Vegasprof 135:Vegasprof 45:Vegasprof 451:Category 380:but the 340:contribs 328:unsigned 53:Notation 430:Erratum 382:Erratum 308:Isn't 143:Finite? 376:space. 259:Oravec 32:scale. 291:David 438:talk 434:yoyo 390:talk 357:talk 336:talk 404:If 106:or 453:: 440:) 392:) 359:) 342:) 338:• 322:of 293:. 133:. 436:( 412:D 410:P 406:D 388:( 355:( 334:( 214:— 201:1 119:X 115:T 94:) 91:X 88:( 85:T 65:X

Index

content assessment
Vegasprof
09:58, 8 November 2006 (UTC)
Vegasprof
20:27, 8 November 2006 (UTC)
Vegasprof
19:05, 9 November 2006 (UTC)
David Eppstein
19:33, 9 November 2006 (UTC)
David Eppstein
22:43, 9 November 2006 (UTC)
Vegasprof
10:04, 10 November 2006 (UTC)
Vegasprof
10:04, 10 November 2006 (UTC)
David Eppstein
16:07, 10 November 2006 (UTC)
Vegasprof
10:04, 10 November 2006 (UTC)
David Eppstein
16:07, 10 November 2006 (UTC)
Vegasprof
21:50, 11 November 2006 (UTC)
Oravec
22:09, 11 November 2006 (UTC)
Tparameter
20:10, 10 November 2006 (UTC)
David
Vegasprof
21:50, 11 November 2006 (UTC)

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