MSE with parallel computation

[aparrar1]

I am using quantregForest with parallel computation and I have noticed that the mean squared error values are not getting calculated when using the parallel option. I am not sure why this is happening, looking at the parallelRandomForest code it looks like mse should be part of the output of the function.

Following the example in the documentation:

library("randomForest")
library("quantregForest")
library("parallel")

data(airquality)
set.seed(1)
airquality <- airquality[ !apply(is.na(airquality), 1,any), ]
n <- nrow(airquality)
indextrain <- sample(1:n,round(0.6*n),replace=FALSE)
Xtrain <- airquality[ indextrain,2:6]
Ytrain <- airquality[ indextrain,1]

qrf <- quantregForest(x=Xtrain, y=Ytrain, keep.inbag = TRUE, importance=TRUE)
qrf$mse
plot(qrf)

qrf <- quantregForest(x=Xtrain, y=Ytrain, keep.inbag = TRUE, importance=TRUE, nthreads=10)
qrf$mse
NULL
plot(qrf)
Error in array(x, c(length(x), 1L), if (!is.null(names(x))) list(names(x), :'data' must be of a vector type, was 'NULL'