1 2 3
The earth object
Force pruning only, no forward pass.
Arguments passed on to
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.
1 2 3 4 5 6 7 8 9 10 11
This automatic determination to do a forward pass can be overridden
ponly=TRUE the forward pass will be skipped and only the pruning pass will be executed.
This is useful for doing a pruning pass with new data.
data argument to specify the new data.)
Typically in this scenario you would also specify
This is because with sufficient new data, independent of the original
training data, the RSS not the GCV should be used for evaluating model
(The GCV approximates what the RSS would be on new data — but here
we actually have new data, so why bother approximating.
This "use new data for pruning" approach is useful in situations where
you don't trust the GCV approximation for your data.)
penalty=-1, earth will calculate the RSS, not the GCV.
See also the description of
penalty on the
earth help page.
Another (somewhat esoteric) use of
ponly=TRUE is to do subset
selection with a different
penalty from that used to build the
update.earth will tell you if earth's
forward pass was skipped.
If you used
keepxy=TRUE in your original call to
update.earth will use the saved values of
unless you specify otherwise by arguments to
It can be helpful to set
trace=1 to see which
is used by
The value is the same as that returned by
object is the only parameter then no changes are made
— the returned value will be the same as the original
1 2 3 4 5 6 7 8 9
Add the following code to your website.
For more information on customizing the embed code, read Embedding Snippets.