Hello all -
I am using S-Plus 7.0 for windows to develop a regression tree as a means to
stratify my predictor variables in a way so that they best predict my
continuous response variable for my dissertation. I have little
S-Plus/Statistics background, so I apologize in advance. Here are a few
questions I have:
1. Is there some value on the summary output that gives goodness-of-fit of the
output tree model?
2. What exactly is deviance/residual mean deviance with respect to tree
models? From what I understand, res. mean deviance is the squared difference
between observed and predicted values, which would mean a lower res. mean
deviance is a better model, is this correct?
3. I understand nodes split where the y-values are statistically different -
is this at 95% confidence? Can this be adjusted?
4. Is there any way to compare tree models to determine which is best to use?
Any help/suggestions would be very very greatly appreciated - thank you in
advance!
-Stephanie
Stephanie Mather
Graduate Research Assistant
University of Connecticut
Dept of Civil & Enviro. Engineering
261 Glenbrook Rd, Unit 2037
Storrs, CT 06269-2037
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