JavaScript/Maths/MeanSquareError.js at master · TheAlgorithms/JavaScript · GitHub

21 lines (15 loc) · 526 Bytes

// Wikipedia: https://en.wikipedia.org/wiki/Mean_squared_error

const meanSquaredError = (predicted, expected) => {

if (!Array.isArray(predicted) || !Array.isArray(expected)) {

throw new TypeError('Argument must be an Array')

}

if (predicted.length !== expected.length) {

throw new TypeError('The two lists must be of equal length')

}

let err = 0

for (let i = 0; i < expected.length; i++) {

err += (expected[i] - predicted[i]) ** 2

}

return err / expected.length

}

export { meanSquaredError }

Expand file tree