影响因子:1.095
     DOI码:10.1016/j.jspi.2018.09.008
    
    
     发表刊物:Journal of Statistical Planning and Inference
    
    
     关键字:Mallows criterion; Threshold model; Weighted-average
     摘要:This paper proposes two types of weighted-averaging estimators of coefficients in segmented linear regressions with a possible threshold. We construct an approximate Mallows criterion which can be looked as an average of limit cases with corresponding threshold effect zero and infinite. Following Hansen (2007) we propose to weightedly average two estimators of coefficients separately with and without threshold effect where weights can be selected by minimizing the Mallows criterion. Further we construct another type of Mallows criterion which is an estimate of the squared error from the model average fit and is used to obtain the new weights for averaging. Under the second Mallows criterion, we find that the new weights make Mallows Model Average (MMA) estimator to be asymptotically optimal in the sense of achieving a lower squared error. Specially in the case of a possible abrupt change, new weights are proved to tend to either one or zero under the true model with only one threshold or tend to 1/2 under the true model without a threshold. Numerical results demonstrate that the proposed MMA estimator performs better under different complicated changes and does choose the true model under one possible abrupt change. (C) 2018 Elsevier B.V. All rights reserved.
    
     论文类型:期刊论文
    
    
    
    
     卷号:200
    
     页面范围:102-118
    
     ISSN号:0378-3758
     是否译文:否
    
    
     收录刊物:SCI
    
     
           第一作者:Dongxue Zhang
     
           通讯作者:Zhiming Xia
