词条 | Bayesian information criterion | ||||||||||
释义 |
In statistics, the Bayesian information criterion (BIC) or Schwarz information criterion (also SIC, SBC, SBIC) is a criterion for model selection among a finite set of models; the model with the lowest BIC is preferred. It is based, in part, on the likelihood function and it is closely related to the Akaike information criterion (AIC). When fitting models, it is possible to increase the likelihood by adding parameters, but doing so may result in overfitting. Both BIC and AIC attempt to resolve this problem by introducing a penalty term for the number of parameters in the model; the penalty term is larger in BIC than in AIC. The BIC was developed by Gideon E. Schwarz and published in a 1978 paper,[1] where he gave a Bayesian argument for adopting it. DefinitionThe BIC is formally defined as[2][3] where
Konishi and Kitigawa (2008, p. 217) derive the BIC to approximate the distribution of the data, integrating out the parameters using Laplace's method, starting with the following: where is the prior for under model . The log(likelihood), , is then expanded to a second order Taylor series about the MLE, , assuming it is twice differentiable as follows: where is the average observed information per observation, and prime () denotes transpose of the vector . To the extent that is negligible and is relatively linear near , we can integrate out to get the following: As increases, we can ignore and as they are . Thus, where BIC is defined as above, and either (a) is the Bayesian posterior mode or (b) uses the MLE and the prior has nonzero slope at the MLE. Then the posterior Properties{{refimprove section|date=November 2011}}
LimitationsThe BIC suffers from two main limitations[4]
Gaussian special caseUnder the assumption that the model errors or disturbances are independent and identically distributed according to a normal distribution and that the boundary condition that the derivative of the log likelihood with respect to the true variance is zero, this becomes (up to an additive constant, which depends only on n and not on the model):[5] where is the error variance. The error variance in this case is defined as which is a biased estimator for the true variance. In terms of the residual sum of squares (RSS) the BIC is When testing multiple linear models against a saturated model, the BIC can be rewritten in terms of the deviance as:[6]where is the number of model parameters in the test. When picking from several models, the one with the lowest BIC is preferred. The BIC is an increasing function of the error variance and an increasing function of k. That is, unexplained variation in the dependent variable and the number of explanatory variables increase the value of BIC. Hence, lower BIC implies either fewer explanatory variables, better fit, or both. The strength of the evidence against the model with the higher BIC value can be summarized as follows:[6]
The BIC generally penalizes free parameters more strongly than the Akaike information criterion, though it depends on the size of n and relative magnitude of n and k. It is important to keep in mind that the BIC can be used to compare estimated models only when the numerical values of the dependent variable are identical for all estimates being compared. The models being compared need not be nested, unlike the case when models are being compared using an F-test or a likelihood ratio test.{{Citation needed|date=February 2019}} BIC for high-dimensional modelFor high dimensional model with the number of potential variables , and the true model size is bounded by a constant, modified BICs has been proposed in Chen and Chen (2008) and Gao and Song (2010). For high dimensional model with the number of variables , and the true model size is unbounded, a high dimensional BIC has been proposed in Gao and Carroll (2017). The high dimensional BIC is of the form: where can be any number greater than zero. Gao and Carroll (2017) proposed a pseudo-likelihood BIC for which the pseudo log-likelihood is used instead of the true log-likelihood. The high dimensional pseudo-likelihood BIC is of the form: where is an estimated degrees of freedom, and the constant is an unknown constant. To achieve the theoretical model selection consistency for divergent , the two high dimensional BICs above require the multiplicative factor . However, in practical use, the high dimensional BIC can take a simpler form: where various choices of the multiplicative factor can be used. In empirical studies, or can be used and it is shown to have good empirical performance. See also
Notes1. ^{{citation | last=Schwarz |first=Gideon E. |title=Estimating the dimension of a model |journal= Annals of Statistics |year=1978 |volume=6 |issue=2 |pages=461–464 |doi=10.1214/aos/1176344136 |mr=468014 }}. 2. ^{{Cite journal| doi = 10.1111/j.1467-9574.2012.00530.x| volume = 66 | issue = 3 | pages = 217–236| last = Wit | first = Ernst |author2=Edwin van den Heuvel |author3=Jan-Willem Romeyn| title = 'All models are wrong...': an introduction to model uncertainty| journal = Statistica Neerlandica| year = 2012}} 3. ^NOTE: The AIC, AICc and BIC defined by Claeskens and Hjort (2008) is the negative of that defined in this article and in most other standard references. 4. ^1 {{cite book|last=Giraud|first=C.|year=2015|title=Introduction to high-dimensional statistics|publisher=Chapman & Hall/CRC|isbn=9781482237948}} 5. ^{{cite book|last=Priestley|first=M.B.|year=1981|title=Spectral Analysis and Time Series|publisher=Academic Press|isbn=978-0-12-564922-3}} (p. 375). 6. ^1 {{Citation| doi = 10.2307/2291091| issn = 0162-1459| volume = 90| issue = 430| pages = 773–795| last1 = Kass| first1 = Robert E.| last2= Raftery| first2= Adrian E.| title = Bayes Factors| journal = Journal of the American Statistical Association| year = 1995| jstor = 2291091}}. References
| title = Information criteria and statistical modeling | publisher = Springer | isbn = 978-0-387-71886-6}}
External links
3 : Model selection|Bayesian inference|Regression variable selection |
||||||||||
随便看 |
|
开放百科全书收录14589846条英语、德语、日语等多语种百科知识,基本涵盖了大多数领域的百科知识,是一部内容自由、开放的电子版国际百科全书。