(numeric())
True (observed) values.
Must have the same length as response.
response
(numeric())
Predicted response values.
Must have the same length as truth.
sample_weights
(numeric())
Vector of non-negative and finite sample weights.
Must have the same length as truth.
The vector gets automatically normalized to sum to one.
Defaults to equal sample weights.
alpha
numeric(1)
The quantile to compute the pinball loss.
...
(any)
Additional arguments. Currently ignored.
Meta Information
Type: "regr"
Range: \((-\infty, \infty)\)
Minimize: TRUE
Required prediction: response
Details
The pinball loss for quantile regression is defined as $$
\text{Average Pinball Loss} = \frac{1}{n} \sum_{i=1}^{n} w_{i}
\begin{cases}
q \cdot (t_i - r_i) & \text{if } t_i \geq r_i \\
(1 - q) \cdot (r_i - t_i) & \text{if } t_i < r_i
\end{cases}
$$
where \(q\) is the quantile and \(w_i\) are normalized sample weights.