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In statistics, the backfitting algorithm is a simple iterative procedure used to fit a generalized additive model. It was introduced in 1985 by Leo Breiman and Jerome Friedman along with generalized additive models. In most cases, the backfitting algorithm is equivalent to the Gauss–Seidel method algorithm for solving a certain linear system of equations ==Algorithm== Additive models are a class of non-parametric regression models of the form: : where each is a variable in our -dimensional predictor , and is our outcome variable. represents our inherent error, which is assumed to have mean zero. The represent unspecified smooth functions of a single . Given the flexibility in the , we typically do not have a unique solution: is left unidentifiable as one can add any constants to any of the and subtract this value from . It is common to rectify this by constraining : for all leaving : necessarily. The backfitting algorithm is then: 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「Backfitting algorithm」の詳細全文を読む スポンサード リンク
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