I am using the randomForest command for regression. I was wondering if there is a way to get the data sample for a single tree when using the `randomForest`

package? I am aware that I can get the structure for a single tree using the `gettree`

command. The returned object contains predicted values for the outcome, and I am trying to find the actual outcome so that I can calculate the MSE for that particular tree. I know that the `randomForest`

object contains this information but it would be neat to do is manually as well.

As per GreyMerchant's request, I've included a reprex below. I use the `airquality`

data set included with R.

```
require(randomForest)
# Make this example reproducible
set.seed(1)
# Fit the random forest model
model <- randomForest(
formula = Ozone ~ .,
data = airquality
)
# Get first tree
tree_1 <- gettree(model, k = 1)
```

Now I would like to somehow get the original data that was used to make predictions for tree number 1. For normal regressions I would simply use the data from the `data`

argument, but from my understanding , a Random Forest model will fit trees using sub-samples of the original data.

I want the original data so that I can manually calculate the output from `model$mse`

.