aov.object
Analysis of Variance Objects

### Description

Classes of objects that result from fitting analysis of variance models. These classes are "aov", "maov", and "aovlist".
Generation
An object of class "aov" represents the fit for a univariate analysis of variance of a single error stratum. Objects of class "maov" are of a single error stratum but have multiple responses. An object of class "aovlist" represents an analysis of variance with multiple strata; it is a list of objects, each of class "aov".
Methods

- The class "aov" includes methods for the following generic functions:
  - coef
  - print
  - se
  - se.contrast
  - summary.
- The class "aovlist" includes methods for the following generic functions:
  - dummy.coef
  - eff
  - print
  - proj
  - se
  - se.contrast
  - summary
  - terms.

Inheritance

Class "aov" | inherits from class "lm".
Class "aovlist" | inherits from "listof".

The inheritance for class "maov" is "maov" "mlm" "aov" "lm".
Structure
The "aov" and "maov" objects are implemented as lists with the following components:
coefficients
the coefficients of the least squares fit of the response(s) on the model matrix. The column names of the matrix of coefficients are the names of the single-degree-of-freedom effects (the linearly independent columns of the model matrix).
residuals
the residuals from the fit.
effects
orthogonal, single-degree-of-freedom effects. Note that these are always an orthogonal transformation of the response. These effects do not depend on any property of the design (for example, balance) for their orthogonality.

| Caution | These are not what is called "the effects in 2 to the k designs." see coefficients for information about those effects.

rank
the computed rank (number of estimable effects) for the model.
fitted.values
the fitted values for the model.
assign
the list of assignments of coefficients (and effects) to the terms in the model. The names of this list are the names of the terms. The ith component of the list is the vector saying which coefficients correspond to the ith term. It might be of length zero if there were no estimable effects for the term.
qr
the QR decomposition from the model fit. This is an object of class "qr" and is of little direct interest to the general user.
df.residual
the number of degrees of freedom for residuals.
contrasts
a list containing sufficient information to construct the contrasts used to fit any factors occurring in the model. The list contains entries that are either matrices or character vectors. When a factor is coded by contrasts, the corresponding contrast matrix is stored in this list. Factors that appear only as dummy variables and variables in the model that are matrices correspond to character vectors in the list. The character vector has the level names for a factor or the column labels for a matrix.
xlevels
a list with an component named for each predictor variable that is a factor listing the levels thereof, and that are actually used in the model.
call
an image of the call that produced the object, but with the arguments all named, and with the actual formula included as the formula argument.
terms
an object of mode "expression" and class "term" summarizing the formula. This is used by various methods, but not typically of direct relevance to users.
model
a data frame with the columns from the original data that were used in the model (both response and predictors). Only included if model = TRUE.
x
optionally the model matrix, if x=TRUE.
y
optionally the response, if y=TRUE.
An object of class "aovlist" is a list of aov or maov objects of the form above (without call or terms components), with each component of the list representing one stratum. This list has attributes call and terms as described above.
See Also
aov, lm.object
Package stats version 6.1.5-18
Package Index