B-factor iterative test

When the EP comprises linear computations (linear in the observations) such as simple differences, y - B, or linear least squares or linear multivariate computations, initial normality (of the observations y) is preserved for the estimated quantities. Non-linear computations, such as arise commonly in iterative model selection and peak search routines, produce estimated parameters having non-normal distributions (59). Caution is in order, in those cases, in applying "normal" values of test statistics to calculate 1 and Cl s. (Other factors to consider are the extent of non-linearity, the level of confidence or significance [1-a], and the robustness of the statistic in question.)... 

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