update.earth {earth}R Documentation

Update an 'earth' model

Description

Update an ‘earth’ model.

Usage

## S3 method for class 'earth':
update(object = stop("no 'object' arg"),
       formula. = NULL, ..., evaluate = TRUE)

Arguments

object
formula.
... These arguments are the same as earth. The formula. argument is treated like earth's formula argument.

evaluate If TRUE (default) evaluate the new call else return the call.

Value

The value is the same as that returned by earth. If object is the only parameter then no changes are made — the returned value will be the same as the original object.

Note

If only the following arguments are used, a forward pass is unnecessary, and update.earth will perform only the pruning pass. This is usually much faster for large models.

     trace
     pmethod
     ppenalty
     nprune
     Get.crit
     Eval.model.subsets
     Print.pruning.pass
     Force.xtx.prune

See Also

earth

Examples

data(ozone1)
(a <- earth(O3 ~ ., data = ozone1, degree = 2))

# yields:
#    Selected 14 of 21 terms, and 8 of 9 predictors
#    Number of terms at each degree of interaction: 1 6 7
#    GCV: 13.74837   RSS: 3662.576   GRSq: 0.7864352   RSq: 0.8265448

update(a, formula = O3 ~ . - temp) # requires forward pass and pruning

# yields:
#    Selected 15 of 21 terms, and 8 of 8 predictors
#    Number of terms at each degree of interaction: 1 5 9
#    GCV: 13.11272   RSS: 3434.579   GRSq: 0.7963093   RSq: 0.8373425

update(a, nprune = 8)              # requires only pruning

# yields:
#    Selected 8 of 21 terms, and 6 of 9 predictors
#    Number of terms at each degree of interaction: 1 5 2
#    GCV: 15.8959    RSS: 4673.984   GRSq: 0.7530759   RSq: 0.7786458

[Package earth version 1.1-4 Index]