Improve WhiteKernel's vague description
@@ -1055,8 +1055,9 @@ class WhiteKernel(StationaryKernelMixin, Kernel):
"""White kernel.
The main use-case of this kernel is as part of a sum-kernel where it
- explains the noise-component of the signal. Tuning its parameter
- corresponds to estimating the noise-level.
+ explains the noise of the signal as independently and identically
+ normally-distributed. The parameter noise_level equals the variance of this
+ noise.
k(x_1, x_2) = noise_level if x_1 == x_2 else 0
@@ -1065,11 +1066,10 @@ class WhiteKernel(StationaryKernelMixin, Kernel):
Parameters
----------
noise_level : float, default: 1.0
- Parameter controlling the noise level
+ Parameter controlling the noise level (variance)
noise_level_bounds : pair of floats >= 0, default: (1e-5, 1e5)
The lower and upper bound on noise_level
-
"""
def __init__(self, noise_level=1.0, noise_level_bounds=(1e-5, 1e5)):
self.noise_level = noise_level
