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81.
F. Jay Breid Richard A. Davis Keh-Shin Lh Murray Rosenblatt 《Journal of multivariate analysis》1991,36(2)
We discuss a maximum likelihood procedure for estimating parameters in possibly noncausal autoregressive processes driven by i.i.d. non-Gaussian noise. Under appropriate conditions, estimates of the parameters that are solutions to the likelihood equations exist and are asymptotically normal. The estimation procedure is illustrated with a simulation study for AR(2) processes. 相似文献
82.
Takahisa Yokoyama 《Annals of the Institute of Statistical Mathematics》1995,47(2):309-320
We consider a parallel profile model which is useful in analyzing parallel growth curves of several groups. The likelihood ratio criterion for a hypothesis concerning the adequacy of a random-effects covariance structure is obtained under the parallel profile model. The likelihood ratio criterion for the hypothesis in the general one-way MANOVA model is also obtained. Asymptotic null distributions of the criteria are derived when the sample size is large. We give a numerical example of these asymptotic results. 相似文献
83.
Emine Sarigllü 《商业与工业应用随机模型》1994,10(1):27-46
Prediction of customer choice behaviour has been a big challenge for marketing researchers. They have adopted various models to represent customers purchase patterns. Some researchers considered simple zero–order models. Others proposed higher–order models to represent explicitly customers tendency to seek [variety] or [reinforcement] as they make repetitive choices. Nevertheless, the question [Which model has the highest probability of representing some future data?] still prevails. The objective of this paper is to address this question. We assess the predictive effectiveness of the well–known customer choice models. In particular, we compare the predictive ability of the [dynamic attribute satiation] (DAS) model due to McAlister (Journal of Consumer Research, 91, pp. 141–150, 1982) with that of the well–known stochastic variety seeking and reinforcement behaviour models. We found that the stochastic [beta binomial] model has the best predictive effectiveness on both simulated and real purchase data. Using simulations, we also assessed the effectiveness of the stochastic models in representing various complex choice processes generated by the DAS. The beta binomial model mimicked the DAS processes the best. In this research we also propose, for the first time, a stochastic choice rule for the DAS model. 相似文献
84.
Space-Time Point-Process Models for Earthquake Occurrences 总被引:5,自引:0,他引:5
Yosihiko Ogata 《Annals of the Institute of Statistical Mathematics》1998,50(2):379-402
Several space-time statistical models are constructed based on both classical empirical studies of clustering and some more speculative hypotheses. Then we discuss the discrimination between models incorporating contrasting assumptions concerning the form of the space-time clusters. We also examine further practical extensions of the model to situations where the background seismicity is spatially non-homogeneous, and the clusters are non-isotropic. The goodness-of-fit of the models, as measured by AIC values, is discussed for two high quality data sets, in different tectonic regions. AIC also allows the details of the clustering structure in space to be clarified. A simulation algorithm for the models is provided, and used to confirm the numerical accuracy of the likelihood calculations. The simulated data sets show the similar spatial distributions to the real ones, but differ from them in some features of space-time clustering. These differences may provide useful indicators of directions for further study. 相似文献
85.
Jing Qin 《Annals of the Institute of Statistical Mathematics》1994,46(1):117-126
We all know that we can use the likelihood ratio statistic to test hypotheses and construct confidence intervals in full parametric models. Recently, Owen (1988,Biometrika,75, 237–249; 1990,Ann. Statist.,18, 90–120) has introduced the empirical likelihood method in nonparametric models. In this paper, we combine these two likelihoods together and use the likelihood ratio to construct confidence intervals in a semiparametric problem, in which one model is parametric, and the other is nonparametric. A version of Wilks's theorem is developed. 相似文献
86.
Yuzo Hosoya 《Annals of the Institute of Statistical Mathematics》1990,42(1):37-49
By means of second-order asymptotic approximation, the paper clarifies the relationship between the Fisher information of first-order asymptotically efficient estimators and their decision-theoretic performance. It shows that if the estimators are modified so that they have the same asymptotic bias, the information amount can be connected with the risk based on convex loss functions in such a way that the greater information loss of an estimator implies its greater risk. The information loss of the maximum likelihood estimator is shown to be minimal in a general set-up. A multinomial model is used for illustration. 相似文献
87.
Input data modeling is a critical component of a successful simulation application. A perspective of the area is given with an emphasis on available probability distributions as models, estimation methods, model selection and discrimination, and goodness of fit. Three specific distribution classes (lambda,S
B
, TES processes) are discussed in some detail to illustrate characteristics that favor input models. Regarding estimation, we argue for maximum likelihood estimation over method of moments and other matching schemes due to intrinsic superior properties (presuming a specific model) and the capability of accommodating messy data types. We conclude with a list of specific research problems and areas warranting additional attention. 相似文献
88.
Shinto Eguchi 《Annals of the Institute of Statistical Mathematics》1986,38(1):385-398
Summary This paper is concerned with estimation for a subfamily of exponential-type, which is a parametric model with sufficient statistics.
The family is associated with a surface in the domain of a sufficient statistic. A new estimator, termed a projection estimator,
is introduced. The key idea of its derivation is to look for a one-to-one transformation of the sufficient statistic so that
the subfamily can be associated with a flat subset in the transformed domain. The estimator is defined by the orthogonal projection
of the transformed statistic onto the flat surface. Here the orthogonality is introduced by the inverse of the estimated variance
matrix of the statistic on the analogy of Mahalanobis's notion (1936,Proc. Nat. Inst. Sci. Ind.,2, 49–55). Thus the projection estimator has an explicit representation with no iterations. On the other hand, the MLE and
classical estimators have to be sought as numerical solutions by some algorithm with a choice of an initial value and a stopping
rule. It is shown that the projection estimator is first-order efficient. The second-order property is also discussed. Some
examples are presented to show the utility of the estimator. 相似文献
89.
In this paper, we study a stationary AR(p)-ARCH(q) model with parameter vectors a and β. We propose a method for computing the maximum likelihood estimator (MLE) of parameters under the nonnegative restriction. A similar method is also proposed for the case that the parameters are restricted by a simple order: α1≥α2≥…≥αq, andβ1≥β2≥…βp. The strong consistency of the above two estimators is discussed. Furthermore, we consider the problem of testing homogeneity of parameters against the simple order restriction. We give the likelihood ratio (LR) test statistic for the testing problem and derive its asymptotic null distribution. 相似文献
90.
针对某厂一压力机架的焊接结构,采用极大似然方法,进行了部分熔透焊接十字接头的拉—拉疲劳试验,得到了该类结构的P-S-N对数曲线。研究了未熔透尺寸对接头的应力集中系数、疲劳强度和试件疲劳破坏形式的影响规律,结果表明,在焊缝与母材等强的情况下,当未熔透尺寸2a/T<0.5时,其疲劳性能无明显减弱;而当未熔透尺寸2a/T>0.5时,则接头的抗疲劳性能有显著的改变。 相似文献