Knowledge (XXG)

Computer experiment

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is known in principle, in practice this is not the case. Many simulators comprise tens of thousands of lines of high-level computer code, which is not accessible to intuition. For some simulations, such as climate models, evaluation of the output for a single set of inputs can require millions of
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The basic idea of this framework is to model the computer simulation as an unknown function of a set of inputs. The computer simulation is implemented as a piece of computer code that can be evaluated to produce a collection of outputs. Examples of inputs to these simulations are coefficients in
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Fehr, Jörg; Heiland, Jan; Himpe, Christian; Saak, Jens (2016). "Best practices for replicability, reproducibility and reusability of computer-based experiments exemplified by model reduction software".
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that represents our prior belief on the structure of the computer model. The use of this philosophy for computer experiments started in the 1980s and is nicely summarized by Sacks et al. (1989)
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are constructed to emulate a physical system. Because these are meant to replicate some aspect of a system in detail, they often do not yield an analytic solution. Therefore, methods such as
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Unlike physical experiments, it is common for computer experiments to have thousands of different input combinations. Because the standard inference requires
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for parametric models. Since a Gaussian process prior has an infinite dimensional representation, the concepts of A and D criteria (see
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are vector quantities, and they can be very large collections of values, often indexed by space, or by time, or by both space and time.
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The typical model for a computer code output is a Gaussian process. For notational simplicity, assume
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Computer experiments have been employed with many purposes in mind. Some of those include:
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is the covariance function. Popular mean functions are low order polynomials and a popular
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where all evidence about the true state of the world is explicitly expressed in the form of
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is a scalar. Owing to the Bayesian framework, we fix our belief that the function
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are often used because experimentation on an earth sized object is impossible.
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is an experiment used to study a computer simulation, also referred to as an
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Bias correction: Use physical data to correct for bias in the simulation.
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is used to make inferences about the system it replicates. For example,
440:{\displaystyle f\sim \operatorname {GP} (m(\cdot ),C(\cdot ,\cdot )),} 115:
Modeling of computer experiments typically uses a Bayesian framework.
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The design of computer experiments has considerable differences from
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of a square matrix of the size of the number of samples (
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While the Bayesian approach is widely used, 8: 16:Experiment used to study computer simulation 769: 641: 628: 627: 625: 605: 534: 511: 500: 472: 452: 381: 357: 328: 287: 255: 235: 206: 186: 166: 138:approaches have been recently discussed 548:{\displaystyle \nu \rightarrow \infty } 495:, which includes both the exponential ( 580:Popular strategies for design include 653:{\displaystyle {\mathcal {O}}(n^{3})} 119:is an interpretation of the field of 7: 181:, the computer simulation itself as 717:Grey box completion and validation 592:Problems with massive sample sizes 542: 14: 529:) and Gaussian covariances (as 43:and other similar disciplines. 647: 634: 559:Design of computer experiments 539: 431: 428: 416: 407: 401: 395: 339: 333: 298: 292: 266: 260: 217: 211: 201:, and the resulting output as 1: 574:and distance based criteria 111:Computer simulation modeling 722:Artificial financial market 31:system. This area includes 831: 682:Uncertainty quantification 83:Uncertainty quantification 692:Gaussian process emulator 620:), the cost grows on the 586:low discrepancy sequences 467:is the mean function and 304:{\displaystyle f(\cdot )} 56:discrete event simulation 734:Santner, Thomas (2003). 582:latin hypercube sampling 522:{\displaystyle \nu =1/2} 780:10.3934/Math.2016.3.261 37:computational chemistry 654: 614: 549: 523: 481: 461: 441: 366: 346: 319:Gaussian process prior 305: 273: 244: 224: 195: 175: 145:the underlying model, 62:solvers are used. A 810:Design of experiments 805:Computational science 697:Design of experiments 662:patent WO2013055257A1 655: 615: 565:design of experiments 550: 524: 482: 462: 442: 367: 347: 306: 274: 245: 225: 196: 176: 157:into a collection of 41:computational biology 33:computational physics 25:simulation experiment 738:. Berlin: Springer. 624: 604: 533: 499: 471: 451: 380: 356: 345:{\displaystyle f(x)} 327: 286: 272:{\displaystyle f(x)} 254: 234: 223:{\displaystyle f(x)} 205: 185: 165: 52:Computer simulations 687:Bayesian statistics 489:covariance function 117:Bayesian statistics 21:computer experiment 707:Monte Carlo method 702:Molecular dynamics 650: 610: 545: 519: 477: 457: 437: 362: 342: 301: 269: 240: 220: 191: 171: 147:initial conditions 129:prior distribution 613:{\displaystyle n} 493:Matern covariance 480:{\displaystyle C} 460:{\displaystyle m} 365:{\displaystyle f} 243:{\displaystyle x} 194:{\displaystyle f} 174:{\displaystyle x} 151:forcing functions 98:Data assimilation 822: 791: 773: 758:AIMS Mathematics 749: 659: 657: 656: 651: 646: 645: 633: 632: 619: 617: 616: 611: 598:matrix inversion 554: 552: 551: 546: 528: 526: 525: 520: 515: 486: 484: 483: 478: 466: 464: 463: 458: 446: 444: 443: 438: 374:Gaussian process 371: 369: 368: 363: 351: 349: 348: 343: 310: 308: 307: 302: 278: 276: 275: 270: 249: 247: 246: 241: 229: 227: 226: 221: 200: 198: 197: 192: 180: 178: 177: 172: 89:Inverse problems 830: 829: 825: 824: 823: 821: 820: 819: 795: 794: 754: 746: 733: 730: 728:Further reading 712:Surrogate model 673: 637: 622: 621: 602: 601: 594: 561: 531: 530: 497: 496: 469: 468: 449: 448: 378: 377: 354: 353: 325: 324: 321: 312:computer hours 284: 283: 252: 251: 232: 231: 203: 202: 183: 182: 163: 162: 113: 76: 49: 17: 12: 11: 5: 828: 826: 818: 817: 812: 807: 797: 796: 793: 792: 764:(3): 261–281. 751: 750: 744: 729: 726: 725: 724: 719: 714: 709: 704: 699: 694: 689: 684: 679: 672: 669: 649: 644: 640: 636: 631: 609: 593: 590: 569:Optimal design 560: 557: 544: 541: 538: 518: 514: 510: 507: 504: 476: 456: 436: 433: 430: 427: 424: 421: 418: 415: 412: 409: 406: 403: 400: 397: 394: 391: 388: 385: 361: 341: 338: 335: 332: 320: 317: 300: 297: 294: 291: 268: 265: 262: 259: 239: 219: 216: 213: 210: 190: 170: 112: 109: 108: 107: 104:Systems design 101: 95: 92: 86: 75: 72: 68:climate models 64:computer model 60:finite element 48: 45: 15: 13: 10: 9: 6: 4: 3: 2: 827: 816: 813: 811: 808: 806: 803: 802: 800: 789: 785: 781: 777: 772: 767: 763: 759: 753: 752: 747: 745:0-387-95420-1 741: 737: 732: 731: 727: 723: 720: 718: 715: 713: 710: 708: 705: 703: 700: 698: 695: 693: 690: 688: 685: 683: 680: 678: 675: 674: 670: 668: 666: 663: 642: 638: 607: 599: 591: 589: 587: 583: 578: 576: 573: 570: 566: 558: 556: 536: 516: 512: 508: 505: 502: 494: 490: 474: 454: 434: 425: 422: 419: 413: 410: 404: 398: 392: 389: 386: 383: 375: 359: 336: 330: 318: 316: 314: 295: 289: 280: 263: 257: 237: 214: 208: 188: 168: 160: 156: 152: 148: 142: 140: 137: 133: 130: 126: 125:probabilities 122: 118: 110: 105: 102: 99: 96: 93: 90: 87: 84: 81: 80: 79: 73: 71: 69: 65: 61: 57: 53: 46: 44: 42: 38: 34: 30: 26: 22: 761: 757: 735: 595: 579: 562: 322: 281: 158: 154: 143: 114: 77: 50: 24: 20: 18: 136:frequentist 815:Simulation 799:Categories 771:1607.01191 677:Simulation 372:follows a 121:statistics 74:Objectives 47:Background 543:∞ 540:→ 537:ν 503:ν 426:⋅ 420:⋅ 405:⋅ 393:⁡ 387:∼ 296:⋅ 282:Although 29:in silico 788:14715031 671:See also 230:. 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Index

in silico
computational physics
computational chemistry
computational biology
Computer simulations
discrete event simulation
finite element
computer model
climate models
Uncertainty quantification
Inverse problems
Data assimilation
Systems design
Bayesian statistics
statistics
probabilities
prior distribution

frequentist

initial conditions
forcing functions

Gaussian process
covariance function
Matern covariance
design of experiments
Optimal design

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