kyphosis {rpart} | R Documentation |

## Data on Children who have had Corrective Spinal Surgery

### Description

The `kyphosis`

data frame has 81 rows and 4 columns.
representing data on children who have had corrective spinal surgery

### Usage

kyphosis

### Format

This data frame contains the following columns:

`Kyphosis`

- a factor with levels
`absent`

`present`

indicating if a kyphosis (a type of deformation)
was present after the operation.
`Age`

- in months
`Number`

- the number of vertebrae involved
`Start`

- the number of the first (topmost) vertebra operated on.

### Source

John M. Chambers and Trevor J. Hastie eds. (1992)
*Statistical Models in S*, Wadsworth and Brooks/Cole,
Pacific Grove, CA 1992.

### Examples

fit <- rpart(Kyphosis ~ Age + Number + Start, data=kyphosis)
fit2 <- rpart(Kyphosis ~ Age + Number + Start, data=kyphosis,
parms=list(prior=c(.65,.35), split='information'))
fit3 <- rpart(Kyphosis ~ Age + Number + Start, data=kyphosis,
control=rpart.control(cp=.05))
par(mfrow=c(1,2))
plot(fit)
text(fit, use.n=TRUE)
plot(fit2)
text(fit2, use.n=TRUE)

[Package

*rpart* version 3.1-22

Index]