R help - Feb 2007 - tree()

Hi
 
I am trying to use tree() to classify movements in a futures contract.  My
data is like this:
 
         diff      dip                  dim             adx
1          0    100.00000    8650.0000    100.00000
2          0     93.18540    2044.5455     93.18540
3          0     90.30995    1549.1169     90.30995
4          1     85.22030     927.0419     85.22030
5          1     85.36084     785.6480     85.36084
6          0     85.72627     663.3814     85.72627
7          0     78.06721     500.1113     78.06721
8          1     69.59398     376.7558     69.59398
9          1     71.15429     307.4533     71.15429
10         1     71.81023     280.6238     71.81023
 
plus another 6000 lines
 
The cpus example works fine and I am trying this:
 
tree.model <- tree(as.factor(indi$diff) ~ indi$dim + indi$dip + indi$adx,
indi[1:4000,])
tree.model
summary(tree.model)
plot(tree.model);  text(tree.model)
 
but I get this:
> tree.model <- tree(as.factor(indi$diff) ~ indi$dim + indi$dip +
indi$adx,
indi[1:4000,])
> tree.model
node), split, n, deviance, yval, (yprob)
      * denotes terminal node
1) root 6023 8346 0 ( 0.513 0.487 ) *
> summary(tree.model)
Classification tree:
tree(formula = as.factor(indi$diff) ~ indi$dim + indi$dip + indi$adx, 
    data = indi[1:4000, ])
Variables actually used in tree construction:
character(0)
Number of terminal nodes:  1 
Residual mean deviance:  1.386 = 8346 / 6022 
Misclassification error rate: 0.487 = 2933 / 6023 
> plot(tree.model);  text(tree.model)
Error in plot.tree(tree.model) : cannot plot singlenode
tree
> 
I'm not getting any sort of tree formed.
I wondered if anyone could point me in the right direction.
Thanks.
Stephen Choularton
 
 
 
 
 
 
 
 

	[[alternative HTML version deleted]]

This is a function of your data and the tuning parameters you chose to 
use.  See ?tree.control.

On Tue, 20 Feb 2007, stephenc wrote:
> Hi
>
> I am trying to use tree() to classify movements in a futures contract.  My
> data is like this:
>
>         diff      dip                  dim             adx
> 1          0    100.00000    8650.0000    100.00000
> 2          0     93.18540    2044.5455     93.18540
> 3          0     90.30995    1549.1169     90.30995
> 4          1     85.22030     927.0419     85.22030
> 5          1     85.36084     785.6480     85.36084
> 6          0     85.72627     663.3814     85.72627
> 7          0     78.06721     500.1113     78.06721
> 8          1     69.59398     376.7558     69.59398
> 9          1     71.15429     307.4533     71.15429
> 10         1     71.81023     280.6238     71.81023
>
> plus another 6000 lines
>
> The cpus example works fine and I am trying this:
>
> tree.model <- tree(as.factor(indi$diff) ~ indi$dim + indi$dip +
indi$adx,
> indi[1:4000,])
Oh, please!  use the data= argument properly.

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595