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正电子发射断层成像中极大似然估计的渐近一致性及应用AI 解读

This paper indicates that a minor modification of the maximum likelihood estimate of Vardi, Shepp and Kaufman can be regarded as a step in the standard nonparametric MLE by the method of sieves and establishes the asymptotic consistency for it. This method of sieves suggests that the number of pixels needs to be in line with the number of detectors in order to avoid poor image reconstructions. A simulation study is also presented to support this suggestion.

若干计数过程广义比例风险模型的信息与渐近效率AI 解读

Proportional hazards models with stochastic baseline hazards and estimators of the relative risk coefficient in these models were proposed by Prentice, Williams and Peterson and by Chang and Hsiung in medical and industrial contexts. The form of the estimating functions recommended varies according to the form of the unknown stochastic baseline hazards. This paper examines the same estimation problem in the context of large-sample theory. It is shown that the proposed…

Cox 偏得分函数的 E 辅助性投影性质AI 解读

This paper shows that Cox's partial score function is the projection of the score function on the (locally) $E$-ancillary subspace for the nuisance parameter (Small and McLeish). This is done by adapting the concepts of (locally) $E$-ancillarity and (locally) $E$-sufficiency for inference functions (McLeish and Small) to an extended Cox's regression model, where the baseline function is allowed to be a predictable process.

通过估计方程进行时间序贯点估计AI 解读

Time-sequential point estimation is studied in the model of fully parametric censored data and Cox's regression model. Both are investigated in the context of counting processes through estimating equations defined by martingales. The concept of information and a related inequality developed in estimating function theory by Godambe are adapted to these models. These suggest some optimality criteria for choosing stopping times as well as estimators. These lead naturally to…