.\" -*- nroff -*- generated from .Rd format
.BG
.FN corCAR1
.TL
Continuous AR(1) Correlation Structure
.DN
This function is a constructor for the `corCAR1' class,
representing an autocorrelation structure of order 1, with a
continuous time covariate. Objects created using this constructor must
be later initialized using the appropriate `initialize'
method.
.CS
corCAR1(value, form, fixed)
.OA
.AG value
the correlation between two observations one unit of time
apart. Must be between 0 and 1. Defaults to 0.2.
.AG form
a one sided formula of the form `~ t', or `~ t | g', specifying a time
covariate `t' and, optionally, a grouping factor `g'. Covariates for
this correlation structure need not be integer valued.  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.
.AG fixed
an optional logical value indicating whether the
coefficients should be allowed to vary in the optimization, or kept
fixed at their initial value. Defaults to `FALSE', in which case
the coefficients are allowed to vary.
.RT
an object of class `corCAR1', representing an autocorrelation
structure of order 1, with a continuous time covariate.
.SH REFERENCES
Box, G.E.P., Jenkins, G.M., and Reinsel G.C. (1994) "Time Series
Analysis: Forecasting and Control", 3rd Edition, Holden-Day.

Jones, R.H. (1993) "Longitudinal Data with Serial Correlation: A
State-space Approach", Chapman and Hall
.SA
`initialize.corStruct'
.EX
## covariate is Time and grouping factor is Mare
cs1 <- corCAR1(0.2, form = ~ Time | Mare)
.KW models
.WR
