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arXiv 1301.3473stat.ME
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一个成分已知的两成分混合线性回归的半参数估计

Semiparametric estimation of a two-component mixture of linear regressions in which one component is known

L. Bordes, I. Kojadinovic, P. Vandekerkhove

摘要:

针对\cite{Van13}中引入的双组分混合模型,提出了一种新的估计方法。该模型由线性回归的两组分混合物组成,其中一组分完全已知,而另一组分的比例、斜率、截距和误差分布未知。尽管对于合理大小的数据集具有良好的性能,但当样本量变大时,\cite{Van13}中提出的方法具有严重的缺点,因为它是基于对比函数的优化,其逐点计算需要O(n^2)运算。在这项工作中得出的方法的适用范围是大得多,因为它依赖于一个方法的时刻估计免费的调整参数,其计算需要O(n)的操作。从理论角度来看,欧几里得参数向量的估计量和c.d. f的半参数估计量的渐进正态性。\在不涉及零对称假设的弱条件下证明了误差的存在性。此外,还给出了c.d.f.的近似置信带。的误差可以使用加权自助计算,其渐近有效性被证明。通过蒙特卡罗实验,在各种情况下的有限样本性能的估计过程进行了研究。所提出的方法被示出在三个真实的数据集上的大小分别为$n=150$,51和176,343。在最后一节中讨论了所考虑的模型的两个扩展:第一个组件的一个额外的尺度参数的模型,和一个以上的解释变量的模型。

英文摘要:

A new estimation method for the two-component mixture model introduced in \cite{Van13} is proposed. This model consists of a two-component mixture of linear regressions in which one component is entirely known while the proportion, the slope, the intercept and the error distribution of the other component are unknown. In spite of good performance for datasets of reasonable size, the method proposed in \cite{Van13} suffers from a serious drawback when the sample size becomes large as it is based on the optimization of a contrast function whose pointwise computation requires O(n^2) operations. The range of applicability of the method derived in this work is substantially larger as it relies on a method-of-moments estimator free of tuning parameters whose computation requires O(n) operations. From a theoretical perspective, the asymptotic normality of both the estimator of the Euclidean parameter vector and of the semiparametric estimator of the c.d.f.\ of the error is proved under weak conditions not involving zero-symmetry assumptions. In addition, an approximate confidence band for the c.d.f.\ of the error can be computed using a weighted bootstrap whose asymptotic validity is proved. The finite-sample performance of the resulting estimation procedure is studied under various scenarios through Monte Carlo experiments. The proposed method is illustrated on three real datasets of size $n=150$, 51 and 176,343, respectively. Two extensions of the considered model are discussed in the final section: a model with an additional scale parameter for the first component, and a model with more than one explanatory variable.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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