| % File src/library/stats/man/coef.Rd |
| % Part of the R package, https://www.R-project.org |
| % Copyright 1995-2017 R Core Team |
| % Distributed under GPL 2 or later |
| |
| \name{coef} |
| \title{Extract Model Coefficients} |
| \alias{coef} |
| \alias{coefficients} |
| \alias{coef.default}% not exported |
| \alias{coef.aov} |
| \usage{ |
| coef(object, \dots) |
| coefficients(object, \dots) |
| \S3method{coef}{default}(object, complete = TRUE, \dots) |
| \S3method{coef}{aov}(object, complete = FALSE, \dots) |
| } |
| \arguments{ |
| \item{object}{an object for which the extraction of model coefficients is |
| meaningful.} |
| \item{complete}{for the default (used for \code{lm}, etc) and |
| \code{aov} methods: |
| logical indicating if the full coefficient vector should be returned |
| also in case of an over-determined system where some coefficients |
| will be set to \code{\link{NA}}, see also \code{\link{alias}}. Note |
| that the default \emph{differs} for \code{\link{lm}()} and |
| \code{\link{aov}()} results.} |
| \item{\dots}{other arguments.} |
| } |
| \description{ |
| \code{coef} is a generic function which extracts model coefficients |
| from objects returned by modeling functions. \code{coefficients} is |
| an \emph{alias} for it. |
| } |
| \details{ |
| All object classes which are returned by model fitting functions |
| should provide a \code{coef} method or use the default one. |
| (Note that the method is for \code{coef} and not \code{coefficients}.) |
| |
| The \code{"aov"} method does not report aliased coefficients (see |
| \code{\link{alias}}) by default where \code{complete = FALSE}. |
| |
| The \code{complete} argument also exists for compatibility with |
| \code{\link{vcov}} methods, and \code{coef} and \code{aov} methods for |
| other classes should typically also keep the \code{complete = *} |
| behavior in sync. By that, with \code{p <- length(coef(obj, complete = TF))}, |
| \code{dim(vcov(obj, complete = TF)) == c(p,p)} will be fulfilled for both |
| \code{complete} settings and the default. |
| } |
| \value{ |
| Coefficients extracted from the model object \code{object}. |
| |
| For standard model fitting classes this will be a named numeric vector. |
| For \code{"maov"} objects (produced by \code{\link{aov}}) it will be a matrix. |
| } |
| \seealso{ |
| \code{\link{fitted.values}} and \code{\link{residuals}} for related methods; |
| \code{\link{glm}}, \code{\link{lm}} for model fitting. |
| } |
| \references{ |
| Chambers, J. M. and Hastie, T. J. (1992) |
| \emph{Statistical Models in S}. |
| Wadsworth & Brooks/Cole. |
| } |
| \examples{ |
| x <- 1:5; coef(lm(c(1:3, 7, 6) ~ x)) |
| } |
| \keyword{regression} |
| \keyword{models} |