Knowledge

Statistical model validation

Source ๐Ÿ“

79:
limited set of data, but data they have strong prior assumptions about, they may consider validating the fit of their model by using a Bayesian framework and testing the fit of their model using various prior distributions. However, if a researcher has a lot of data and is testing multiple nested models, these conditions may lend themselves toward cross validation and possibly a leave one out test. These are two abstract examples and any actual model validation will have to consider far more intricacies than describes here but these example illustrate that model validation methods are always going to be circumstantial.
188: 153:. The three causes are these: lack of data; lack of control of the input variables; uncertainty about the underlying probability distributions and correlations. The usual methods for dealing with difficulties in validation include the following: checking the assumptions made in constructing the model; examining the available data and related model outputs; applying expert judgment. Note that expert judgment commonly requires expertise in the application area. 102:). This method involves using analyses of the models closeness to the data and trying to understand how well the model predicts its own data. One example of this method is in Figure 1, which shows a polynomial function fit to some data. We see that the polynomial function does not conform well to the data, which appears linear, and might invalidate this polynomial model. 252:
Cross validation is a method of sampling that involves leaving some parts of the data out of the fitting process and then seeing whether those data that are left out are close or far away from where the model predicts they would be. What that means practically is that cross validation techniques fit
105:
Commonly, statistical models on existing data are validated using a validation set, which may also be referred to as a holdout set. A validation set is a set of data points that the user leaves out when fitting a statistical model. After the statistical model is fitted, the validation set is used as
38:
is appropriate or not. Oftentimes in statistical inference, inferences from models that appear to fit their data may be flukes, resulting in a misunderstanding by researchers of the actual relevance of their model. To combat this, model validation is used to test whether a statistical model can hold
78:
Model validation comes in many forms and the specific method of model validation a researcher uses is often a constraint of their research design. To emphasize, what this means is that there is no one-size-fits-all method to validating a model. For example, if a researcher is operating with a very
138:
A model can be validated only relative to some application area. A model that is valid for one application might be invalid for some other applications. As an example, consider the curve in Figure 1: if the application only used inputs from the interval , then the curve might well be an
110: 222:
to determine whether the residuals seem to be effectively random. Such analyses typically requires estimates of the probability distributions for the residuals. Estimates of the residuals' distributions can often be obtained by repeatedly running the model, i.e. by using repeated
126:
If new data becomes available, an existing model can be validated by assessing whether the new data is predicted by the old model. If the new data is not predicted by the old model, then the model might not be valid for the researcher's goals.
253:
the model many, many times with a portion of the data and compares each model fit to the portion it did not use. If the models very rarely describe the data that they were not trained on, then the model is probably wrong.
43:, the process of discriminating between multiple candidate models: model validation does not concern so much the conceptual design of models as it tests only the consistency between a chosen model and its stated outputs. 375:
Feng, Cheng; Zhong, Chaoliang; Wang, Jie; Zhang, Ying; Sun, Jun; Yokota, Yasuto (July 2022). "Learning Unforgotten Domain-Invariant Representations for Online Unsupervised Domain Adaptation".
160:
obtaining real data: e.g. for the curve in Figure 1, an expert might well be able to assess that a substantial extrapolation will be invalid. Additionally, expert judgment can be used in
54:
is a method of model validation that iteratively refits the model, each time leaving out just a small sample and comparing whether the samples left out are predicted by the model: there are
130:
With this in mind, a modern approach is to validate a neural network is to test its performance on domain-shifted data. This ascertains if the model learned domain-invariant features.
82:
In general, models can be validated using existing data or with new data, and both methods are discussed more in the following subsections, and a note of caution is provided, too.
473:
Batzel, J. J.; Bachar, M.; Karemaker, J. M.; Kappel, F. (2013), "Chapter 1: Merging mathematical and physiological knowledge", in Batzel, J. J.; Bachar, M.; Kappel, F. (eds.),
415: 167:
For some classes of statistical models, specialized methods of performing validation are available. As an example, if the statistical model was obtained via a
106:
a measure of the model's error. If the model fits well on the initial data but has a large error on the validation set, this is a sign of overfitting.
458: 424:
Assessing the Reliability of Complex Models: Mathematical and statistical foundations of verification, validation, and uncertainty quantification
624: 50:
plot the difference between the actual data and the model's predictions: correlations in the residual plots may indicate a flaw in the model.
571: 164:-type tests, where experts are presented with both real data and related model outputs and then asked to distinguish between the two. 20: 443: 394: 506: 149: 602: 478: 235: 199: 55: 597:(2002), "Chapter 3: Approximate models", in Huber-Carol, C.; Balakrishnan, N.; Nikulin, M. S.; Mesbah, M. (eds.), 113:
Data (black dots), which was generated via the straight line and some added noise, is perfectly fitted by a curvy
347: 329: 660: 269: 247: 228: 51: 379:. California: International Joint Conferences on Artificial Intelligence Organization. pp. 2958โ€“2965. 67: 655: 338: 172: 278: โ€“ Methods used to determine how well the parameters of a model are estimated by experimental data 427: 275: 147:
When doing a validation, there are three notable causes of potential difficulty, according to the
39:
up to permutations in the data. This topic is not to be confused with the closely related task of
616: 47: 353: 323: 224: 586: 527: 317: 287: 263: 219: 95: 59: 8: 558:
Barlas, Y. (1996), "Formal aspects of model validity and validation in system dynamics",
377:
Proceedings of the Thirty-First International Joint Conference on Artificial Intelligence
168: 540: 511: 452: 439: 390: 281: 63: 35: 567: 536: 482: 431: 380: 308: 284: โ€“ Extent to which a piece of evidence supports a claim about cause and effect 290: โ€“ Statistical property which a model must satisfy to allow precise inference 91: 40: 486: 637: 594: 326: โ€“ Apparent, but false, correlation between causally-independent variables 385: 649: 156:
Expert judgment can sometimes be used to assess the validity of a prediction
341: โ€“ Task of selecting a statistical model from a set of candidate models 320: โ€“ Study of uncertainty in the output of a mathematical model or system 632: 578: 419: 572:
10.1002/(SICI)1099-1727(199623)12:3<183::AID-SDR103>3.0.CO;2-4
501: 296: 161: 187: 19:"Model validation" redirects here. For the investment banking role, see 302: 114: 27: 435: 16:
Evaluating whether a chosen statistical model is appropriate or not
311: โ€“ Form of modelling that uses statistics to predict outcomes 109: 238:
exist and may be used; such diagnostics have been well studied.
525:
Mayer, D. G.; Butler, D.G. (1993), "Statistical validation",
500:
Deaton, M. L. (2006), "Simulation models, validation of", in
234:
If the statistical model was obtained via a regression, then
356: โ€“ Extent to which a measurement corresponds to reality 472: 350: โ€“ Part of the process of building a statistical model 414: 90:
Validation based on existing data involves analyzing the
633:"What are core statistical model validation techniques?" 21:
Quantitative analysis (finance) ยง Model validation
343:
Pages displaying short descriptions of redirect targets
313:
Pages displaying short descriptions of redirect targets
292:
Pages displaying short descriptions of redirect targets
334:
Pages displaying wikidata descriptions as a fallback
581:; Hardin, J. W. (2012), "Chapter 15: Validation", 475:Mathematical Modeling and Validation in Physiology 374: 62:is used to compare simulated data to actual data. 647: 85: 272: โ€“ Statistical model validation technique 218:Residual diagnostics comprise analyses of the 457:: CS1 maint: multiple names: authors list ( 420:"Chapter 5: Model validation and prediction" 524: 121: 34:is the task of evaluating whether a chosen 577: 384: 142: 99: 46:There are many ways to validate a model. 599:Goodness-of-Fit Tests and Model Validity 108: 66:involves fitting the model to new data. 617:How can I tell if a model fits my data? 410: 408: 406: 299: โ€“ Flaw in mathematical modelling 178: 648: 557: 499: 94:of the model or analyzing whether the 630: 593: 305: โ€“ Concept in information theory 507:Encyclopedia of Statistical Sciences 493: 403: 231:for random variables in the model). 182: 150:Encyclopedia of Statistical Sciences 133: 518: 466: 241: 13: 551: 175:exist and are generally employed. 70:estimates the quality of a model. 14: 672: 610: 186: 171:, then specialized analyses for 621:Handbook of Statistical Methods 348:Statistical model specification 330:Statistical conclusion validity 236:regression-residual diagnostics 368: 266: โ€“ Aphorism in statistics 56:many kinds of cross validation 1: 361: 270:Cross-validation (statistics) 248:Cross-validation (statistics) 229:pseudorandom number generator 86:Validation with existing data 631:Hicks, Dan (July 14, 2017). 541:10.1016/0304-3800(93)90105-2 68:Akaike information criterion 7: 583:Common Errors in Statistics 487:10.1007/978-3-642-32882-4_1 339:Statistical model selection 256: 173:regression model validation 73: 10: 677: 245: 18: 416:National Research Council 428:National Academies Press 332: โ€“ statistical test 276:Identifiability analysis 122:Validation with new data 98:seem to be random (i.e. 386:10.24963/ijcai.2022/410 560:System Dynamics Review 504:; et al. (eds.), 225:stochastic simulations 143:Methods for validating 118: 661:Validity (statistics) 587:John Wiley & Sons 354:Validity (statistics) 324:Spurious relationship 246:Further information: 112: 60:Predictive simulation 528:Ecological Modelling 318:Sensitivity analysis 288:Model identification 264:All models are wrong 179:Residual diagnostics 100:residual diagnostics 585:(Fourth ed.), 64:External validation 656:Statistical models 589:, pp. 277โ€“285 430:, pp. 52โ€“85, 426:, Washington, DC: 198:. You can help by 139:acceptable model. 119: 481:, pp. 3โ€“19, 445:978-0-309-25634-6 396:978-1-956792-00-3 282:Internal validity 216: 215: 134:A note of caution 36:statistical model 668: 642: 606: 605:, pp. 25โ€“41 590: 574: 545: 543: 522: 516: 514: 497: 491: 489: 470: 464: 462: 456: 448: 412: 401: 400: 388: 372: 344: 335: 314: 309:Predictive model 293: 242:Cross validation 211: 208: 190: 183: 52:Cross validation 32:model validation 676: 675: 671: 670: 669: 667: 666: 665: 646: 645: 613: 554: 552:Further reading 549: 548: 523: 519: 498: 494: 471: 467: 450: 449: 446: 413: 404: 397: 373: 369: 364: 359: 342: 333: 312: 291: 259: 250: 244: 212: 206: 203: 196:needs expansion 181: 145: 136: 124: 92:goodness of fit 88: 76: 41:model selection 24: 17: 12: 11: 5: 674: 664: 663: 658: 644: 643: 638:Stack Exchange 628: 612: 611:External links 609: 608: 607: 591: 575: 566:(3): 183โ€“210, 553: 550: 547: 546: 535:(1โ€“2): 21โ€“32, 517: 492: 465: 444: 436:10.17226/13395 402: 395: 366: 365: 363: 360: 358: 357: 351: 345: 336: 327: 321: 315: 306: 300: 294: 285: 279: 273: 267: 260: 258: 255: 243: 240: 214: 213: 193: 191: 180: 177: 144: 141: 135: 132: 123: 120: 87: 84: 75: 72: 48:Residual plots 15: 9: 6: 4: 3: 2: 673: 662: 659: 657: 654: 653: 651: 640: 639: 634: 629: 626: 622: 618: 615: 614: 604: 600: 596: 592: 588: 584: 580: 576: 573: 569: 565: 561: 556: 555: 542: 538: 534: 530: 529: 521: 513: 509: 508: 503: 496: 488: 484: 480: 476: 469: 460: 454: 447: 441: 437: 433: 429: 425: 421: 417: 411: 409: 407: 398: 392: 387: 382: 378: 371: 367: 355: 352: 349: 346: 340: 337: 331: 328: 325: 322: 319: 316: 310: 307: 304: 301: 298: 295: 289: 286: 283: 280: 277: 274: 271: 268: 265: 262: 261: 254: 249: 239: 237: 232: 230: 227:(employing a 226: 221: 210: 207:February 2019 201: 197: 194:This section 192: 189: 185: 184: 176: 174: 170: 165: 163: 159: 154: 152: 151: 140: 131: 128: 116: 111: 107: 103: 101: 97: 93: 83: 80: 71: 69: 65: 61: 57: 53: 49: 44: 42: 37: 33: 29: 22: 636: 620: 598: 595:Huber, P. J. 582: 563: 559: 532: 526: 520: 505: 495: 474: 468: 423: 376: 370: 251: 233: 217: 204: 200:adding to it 195: 166: 157: 155: 148: 146: 137: 129: 125: 104: 89: 81: 77: 45: 31: 25: 579:Good, P. I. 297:Overfitting 650:Categories 362:References 303:Perplexity 169:regression 115:polynomial 28:statistics 220:residuals 96:residuals 603:Springer 502:Kotz, S. 479:Springer 453:citation 418:(2012), 257:See also 74:Overview 619: โ€” 158:without 442:  393:  162:Turing 512:Wiley 625:NIST 459:link 440:ISBN 391:ISBN 568:doi 537:doi 483:doi 432:doi 381:doi 202:. 26:In 652:: 635:. 601:, 564:12 562:, 533:68 531:, 510:, 477:, 455:}} 451:{{ 438:, 422:, 405:^ 389:. 58:. 30:, 641:. 627:) 623:( 570:: 544:. 539:: 515:. 490:. 485:: 463:. 461:) 434:: 399:. 383:: 209:) 205:( 117:. 23:.

Index

Quantitative analysis (finance) ยง Model validation
statistics
statistical model
model selection
Residual plots
Cross validation
many kinds of cross validation
Predictive simulation
External validation
Akaike information criterion
goodness of fit
residuals
residual diagnostics

polynomial
Encyclopedia of Statistical Sciences
Turing
regression
regression model validation

adding to it
residuals
stochastic simulations
pseudorandom number generator
regression-residual diagnostics
Cross-validation (statistics)
All models are wrong
Cross-validation (statistics)
Identifiability analysis
Internal validity

Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.

โ†‘