SVR
Epsilon-Support Vector Regression.
The free parameters in the model are C and epsilon.
The implementation is based on libsvm. The fit time complexity is more than quadratic with the number of samples which makes it hard to scale to datasets with more than a couple of 10000 samples. For large datasets consider using LinearSVR
or SGDRegressor
instead, possibly after a Nystroem
transformer or other Kernel Approximation.
Read more in the User Guide.
Python Reference (opens in a new tab)
Constructors
constructor()
Signature
new SVR(opts?: object): SVR;
Parameters
Name | Type | Description |
---|---|---|
opts? | object | - |
opts.C? | number | Regularization parameter. The strength of the regularization is inversely proportional to C. Must be strictly positive. The penalty is a squared l2 penalty. Default Value 1 |
opts.cache_size? | number | Specify the size of the kernel cache (in MB). Default Value 200 |
opts.coef0? | number | Independent term in kernel function. It is only significant in ‘poly’ and ‘sigmoid’. Default Value 0 |
opts.degree? | number | Degree of the polynomial kernel function (‘poly’). Must be non-negative. Ignored by all other kernels. Default Value 3 |
opts.epsilon? | number | Epsilon in the epsilon-SVR model. It specifies the epsilon-tube within which no penalty is associated in the training loss function with points predicted within a distance epsilon from the actual value. Must be non-negative. Default Value 0.1 |
opts.gamma? | number | "auto" | "scale" | Kernel coefficient for ‘rbf’, ‘poly’ and ‘sigmoid’. Default Value 'scale' |
opts.kernel? | "sigmoid" | "precomputed" | "linear" | "poly" | "rbf" | Specifies the kernel type to be used in the algorithm. If none is given, ‘rbf’ will be used. If a callable is given it is used to precompute the kernel matrix. Default Value 'rbf' |
opts.max_iter? | number | Hard limit on iterations within solver, or -1 for no limit. Default Value -1 |
opts.shrinking? | boolean | Whether to use the shrinking heuristic. See the User Guide. Default Value true |
opts.tol? | number | Tolerance for stopping criterion. Default Value 0.001 |
opts.verbose? | boolean | Enable verbose output. Note that this setting takes advantage of a per-process runtime setting in libsvm that, if enabled, may not work properly in a multithreaded context. Default Value false |
Returns
Defined in: generated/svm/SVR.ts:27 (opens in a new tab)
Properties
_isDisposed
boolean
=false
Defined in: generated/svm/SVR.ts:25 (opens in a new tab)
_isInitialized
boolean
=false
Defined in: generated/svm/SVR.ts:24 (opens in a new tab)
_py
PythonBridge
Defined in: generated/svm/SVR.ts:23 (opens in a new tab)
id
string
Defined in: generated/svm/SVR.ts:20 (opens in a new tab)
opts
any
Defined in: generated/svm/SVR.ts:21 (opens in a new tab)
Accessors
class_weight_
Multipliers of parameter C for each class. Computed based on the class\_weight
parameter.
Signature
class_weight_(): Promise<ArrayLike>;
Returns
Promise
<ArrayLike
>
Defined in: generated/svm/SVR.ts:318 (opens in a new tab)
dual_coef_
Coefficients of the support vector in the decision function.
Signature
dual_coef_(): Promise<ArrayLike[]>;
Returns
Promise
<ArrayLike
[]>
Defined in: generated/svm/SVR.ts:341 (opens in a new tab)
feature_names_in_
Names of features seen during fit. Defined only when X
has feature names that are all strings.
Signature
feature_names_in_(): Promise<ArrayLike>;
Returns
Promise
<ArrayLike
>
Defined in: generated/svm/SVR.ts:431 (opens in a new tab)
fit_status_
0 if correctly fitted, 1 otherwise (will raise warning)
Signature
fit_status_(): Promise<number>;
Returns
Promise
<number
>
Defined in: generated/svm/SVR.ts:363 (opens in a new tab)
intercept_
Constants in decision function.
Signature
intercept_(): Promise<ArrayLike>;
Returns
Promise
<ArrayLike
>
Defined in: generated/svm/SVR.ts:386 (opens in a new tab)
n_features_in_
Number of features seen during fit.
Signature
n_features_in_(): Promise<number>;
Returns
Promise
<number
>
Defined in: generated/svm/SVR.ts:408 (opens in a new tab)
n_iter_
Number of iterations run by the optimization routine to fit the model.
Signature
n_iter_(): Promise<number>;
Returns
Promise
<number
>
Defined in: generated/svm/SVR.ts:454 (opens in a new tab)
py
Signature
py(): PythonBridge;
Returns
PythonBridge
Defined in: generated/svm/SVR.ts:109 (opens in a new tab)
Signature
py(pythonBridge: PythonBridge): void;
Parameters
Name | Type |
---|---|
pythonBridge | PythonBridge |
Returns
void
Defined in: generated/svm/SVR.ts:113 (opens in a new tab)
shape_fit_
Array dimensions of training vector X
.
Signature
shape_fit_(): Promise<any[]>;
Returns
Promise
<any
[]>
Defined in: generated/svm/SVR.ts:476 (opens in a new tab)
support_
Indices of support vectors.
Signature
support_(): Promise<ArrayLike>;
Returns
Promise
<ArrayLike
>
Defined in: generated/svm/SVR.ts:498 (opens in a new tab)
support_vectors_
Support vectors.
Signature
support_vectors_(): Promise<ArrayLike[]>;
Returns
Promise
<ArrayLike
[]>
Defined in: generated/svm/SVR.ts:520 (opens in a new tab)
Methods
dispose()
Disposes of the underlying Python resources.
Once dispose()
is called, the instance is no longer usable.
Signature
dispose(): Promise<void>;
Returns
Promise
<void
>
Defined in: generated/svm/SVR.ts:171 (opens in a new tab)
fit()
Fit the SVM model according to the given training data.
Signature
fit(opts: object): Promise<any>;
Parameters
Name | Type | Description |
---|---|---|
opts | object | - |
opts.X? | ArrayLike | Training vectors, where n\_samples is the number of samples and n\_features is the number of features. For kernel=”precomputed”, the expected shape of X is (n_samples, n_samples). |
opts.sample_weight? | ArrayLike | Per-sample weights. Rescale C per sample. Higher weights force the classifier to put more emphasis on these points. |
opts.y? | ArrayLike | Target values (class labels in classification, real numbers in regression). |
Returns
Promise
<any
>
Defined in: generated/svm/SVR.ts:188 (opens in a new tab)
init()
Initializes the underlying Python resources.
This instance is not usable until the Promise
returned by init()
resolves.
Signature
init(py: PythonBridge): Promise<void>;
Parameters
Name | Type |
---|---|
py | PythonBridge |
Returns
Promise
<void
>
Defined in: generated/svm/SVR.ts:122 (opens in a new tab)
predict()
Perform regression on samples in X.
For an one-class model, +1 (inlier) or -1 (outlier) is returned.
Signature
predict(opts: object): Promise<ArrayLike>;
Parameters
Name | Type | Description |
---|---|---|
opts | object | - |
opts.X? | ArrayLike | For kernel=”precomputed”, the expected shape of X is (n_samples_test, n_samples_train). |
Returns
Promise
<ArrayLike
>
Defined in: generated/svm/SVR.ts:236 (opens in a new tab)
score()
Return the coefficient of determination of the prediction.
The coefficient of determination \(R^2\) is defined as \((1 - \frac{u}{v})\), where \(u\) is the residual sum of squares ((y\_true \- y\_pred)\*\* 2).sum()
and \(v\) is the total sum of squares ((y\_true \- y\_true.mean()) \*\* 2).sum()
. The best possible score is 1.0 and it can be negative (because the model can be arbitrarily worse). A constant model that always predicts the expected value of y
, disregarding the input features, would get a \(R^2\) score of 0.0.
Signature
score(opts: object): Promise<number>;
Parameters
Name | Type | Description |
---|---|---|
opts | object | - |
opts.X? | ArrayLike [] | Test samples. For some estimators this may be a precomputed kernel matrix or a list of generic objects instead with shape (n\_samples, n\_samples\_fitted) , where n\_samples\_fitted is the number of samples used in the fitting for the estimator. |
opts.sample_weight? | ArrayLike | Sample weights. |
opts.y? | ArrayLike | True values for X . |
Returns
Promise
<number
>
Defined in: generated/svm/SVR.ts:271 (opens in a new tab)