[ksa]

    const X1 = 6.903 + 0.047 * v1;
    const X2 = 0.553 * pol;
    const X3 = 0.614 * pol1;
    const X4 = 0.536 * pol5;
    const X5 = 1.149 * pol2;
    const X6 = 0.734 * pol3;
    const X7 = 1.03 * pol4;
    const X = X1 + X2 + X3 + X4 + X5 + X6 + X7;

Зачем столько констант?

let X = 6.903 + 0.047 * v1;
X += 0.553 * pol;
X += 0.614 * pol1;
X += 0.536 * pol5;
X += 1.149 * pol2;
X += 0.734 * pol3;
X += 1.03 * pol4;
X = 1+Math.exp(-X);
X = 1/(1+X);