## Linear versus quadratic estimators in linearized models.(English)Zbl 1099.62523

Summary: In nonlinear regression models an approximate value of an unknown parameter is frequently at our disposal. Then the linearization of the model is used and a linear estimate of the parameter can be calculated. Some criteria how to recognize whether a linearization is possible are developed. In the case that they are not satisfied, it is necessary to take into account either some quadratic corrections or to use the nonlinear least squares method. The aim of the paper is to find some criteria for an ordering linear and quadratic estimators.

### MSC:

 62J02 General nonlinear regression 62J05 Linear regression; mixed models 62F10 Point estimation

### Keywords:

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