corCompSymm(value, form)
value
| the correlation between any two correlated observations. Defaults to 0. |
form
|
a one sided formula of the form ~ t , or code{~ t |
g}, specifying a time covariate t and, optionally, a
grouping factor g . When a grouping factor is present in
form , the correlation structure is assumed to apply only
to observations within the same grouping level; observations with
different grouping levels are assumed to be uncorrelated. Defaults to
~ 1 , which corresponds to using the order of the observations
in the data as a covariate, and no groups.
|
corCompSymm
class,
representing a compound symmetry structure corresponding to uniform
correlation. Objects created using this constructor need to be later
initialized using the appropriate initialize
method.corCompSymm
, representing a compound
symmetry correlation structure.initialize.corStruct
library(lme) ## covariate is observation order and grouping factor is Subject cs1 <- corCompSymm(0.5, form = ~ 1 | Subject)