6 parameter model. Learns xor blazing fast.

xorModel.js

const data = [
    [
        [0, 0], 1
    ],
    [
        [0, 1], 0
    ],
    [
        [1, 0], 0
    ],
    [
        [1, 1], 1
    ]
];
const sigmoid = x => 1 / (1 + Math.exp(-x));
const sigmoid_ = x => sigmoid(x) * (1 - sigmoid(x));
const randWeight = () => Math.random() * 2 - 1;
let m0 = randWeight();
let m1 = randWeight();
let b0 = randWeight();
let a = randWeight();
let b = randWeight();
let c = randWeight();
const learningRate = 0.01;
for (let iteration = 0; iteration < 100000; iteration++) {
    const m0nudges = [];
    const m1nudges = [];
    const b0nudges = [];
    const anudges = [];
    const bnudges = [];
    const cnudges = [];
    data.forEach(([
        [x0, x1], y
    ]) => {
        const W = m0 * x0 + m1 * x1 + b0;
        const X = a * W ** 2 + b * W + c;
        const Z = sigmoid(X);
        const C = ((Z - y) ** 2) / 2;
        m0nudges.push((Z - y) * sigmoid_(X) * (2 * a * W + b) * x0);
        m1nudges.push((Z - y) * sigmoid_(X) * (2 * a * W + b) * x1);
        b0nudges.push((Z - y) * sigmoid_(X) * (2 * a * W + b));
        anudges.push((Z - y) * sigmoid_(X) * W ** 2);
        bnudges.push((Z - y) * sigmoid_(X) * W);
        cnudges.push((Z - y) * sigmoid_(X));
    });
    m0 += -R.mean(m0nudges) * learningRate;
    m1 += -R.mean(m1nudges) * learningRate;
    b0 += -R.mean(b0nudges) * learningRate;
    a += -R.mean(anudges) * learningRate;
    b += -R.mean(bnudges) * learningRate;
    c += -R.mean(cnudges) * learningRate;
}

function runModel(x0, x1) {
    const W = m0 * x0 + m1 * x1 + b0;
    const X = a * W ** 2 + b * W + c;
    const Z = sigmoid(X);
    return Z;
}
console.log(runModel(0, 0));
console.log(runModel(0, 1));
console.log(runModel(1, 0));
console.log(runModel(1, 1));