/**
 * Welford's online algorithm for computing running statistics in O(1) memory.
 * No arrays needed — maintains mean, variance, min, max incrementally.
 */
export declare class RunningStats {
    private n;
    private m;
    private m2;
    private lo;
    private hi;
    push(value: number): void;
    getMean(): number;
    getStddev(): number;
    getMin(): number;
    getMax(): number;
    getCount(): number;
    reset(): void;
    toJSON(): {
        mean: number;
        stddev: number;
        min: number;
        max: number;
        count: number;
    };
}