import { RegressorBase } from '../base';
import { Params } from '../base/estimator';
import { SubsetSizeOption } from '../utils/paramResolvers';
export interface ExtraTreeRegressorProps {
    max_depth?: number;
    min_samples_split?: number;
    splitter?: 'random';
    max_features?: SubsetSizeOption;
    randomState?: number;
}
export declare class ExtraTreeRegressor extends RegressorBase {
    private feature_number;
    private regTree;
    private min_samples_split;
    private max_depth;
    private splitter;
    private max_features;
    private randomState?;
    private random;
    constructor(props?: ExtraTreeRegressorProps);
    getParams(): Params;
    private getFeatureSubset;
    private calErr;
    private attributeSelection;
    private initTreeNode;
    private buildTree;
    fit(sampleX: number[][], sampleY: number[]): void;
    private findSample;
    predict(sampleX: number[][]): number[];
    get featureImportances(): number[];
    getRawFeatureImportances(): number[];
}