之所以出现这个困惑,在于CAMERON 在'"Microeconometrics : Methods and Applications"一书中关于M-类估计的一个注释,原文如下:
The term m-estimator, attributed to Huber (1967), is interpreted as an abbreviation
for maximum-likelihood-like estimator. Many econometrics authors, including Amemiya (1985, p. 105), Greene (2003, p. 461), andWooldridge (2002, p. 344), define an m-estimator as optimizing over a sum of terms, as in (5.4). Other authors, including Serfling (1980), define an m-estimator as solutions of quations such as (5.5). Huber (1967) considered both cases and Huber (1981, p. 43) explicitly defined an m-estimator in both ways. In this book we call the former type of estimator an m-estimator and the latter an estimating equations estimator (which will be treated separately in Section 5.4).
知道ML 与 NLS均是M-类估计的典型代表.但对于OLS是不是M-类估计,与同学发生了分歧.根据2# bobguy 的说明,现下已经有了判断!再谢!
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