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WhiteKernel

Defined in: ml/kernels/white.js:32

Abstract base class for GP kernels

Extends

Constructors

Constructor

new WhiteKernel(noiseLevelOrOpts?): WhiteKernel

Defined in: ml/kernels/white.js:45

Parameters

noiseLevelOrOpts?

any = 1.0

Noise variance, or an options object { noiseLevel, noiseLevelBounds } (aliases: noise_level, variance, noise_level_bounds). noiseLevelBounds is [low, high], honoured by hyperparameter optimization; a floor is the usual reason to set it, since marginal likelihood with many ARD length scales can drive the noise to zero and explain everything through the kernel.

Returns

WhiteKernel

Example

new WhiteKernel(0.1)
new WhiteKernel({ noiseLevel: 0.1, noiseLevelBounds: [0.05, 2] })

Overrides

Kernel.constructor

Properties

noiseLevel

noiseLevel: any

Defined in: ml/kernels/white.js:49


noiseLevelBounds

noiseLevelBounds: any

Defined in: ml/kernels/white.js:54

Methods

call()

call(X1, X2?): Matrix

Defined in: ml/kernels/white.js:76

noiseLevel·I for K(X, X), all zeros for a cross-covariance K(X1, X2). Overridden rather than left to the base pointwise loop so the distinction rests on which matrix is being built, not on row identity.

Parameters

X1

any

X2?

any = null

Returns

Matrix

Overrides

Kernel.call


clone()

clone(): Kernel

Defined in: ml/kernels/base.js:87

Clone the kernel with the same parameters

Returns

Kernel

New kernel instance

Inherited from

Kernel.clone


compute()

compute(x1, x2): any

Defined in: ml/kernels/white.js:67

Covariance between two observations. noiseLevel only when they are the same observation — identified by reference, not by value, since the whole point of white noise is that two readings of the same input are still independent. Callers that mean “the variance at this point” pass the same row twice (compute(x, x)), which is exactly the diagonal case.

Parameters

x1

any

x2

any

Returns

any

Overrides

Kernel.compute


getParams()

getParams(): object

Defined in: ml/kernels/white.js:90

Get kernel hyperparameters

Returns

object

Hyperparameters

noiseLevel

noiseLevel: any

Overrides

Kernel.getParams


setParams()

setParams(params): void

Defined in: ml/kernels/white.js:96

Set kernel hyperparameters

Parameters

params

New parameters

noise_level

any

noiseLevel

any

variance

any

Returns

void

Overrides

Kernel.setParams