A Vignette for Package Polydect

But in reality, our observations will also contain noises. And here for simplicity, we assume the noises 2i’s are independent and identically distributed random errors with E(2i) = 0 and V ar(2i) = σ(Xi). But for simplicity, here we just assume that the noise level for all the design points are the same. So we have Yi| Xi = f(Xi) + 2i, i = 1, 2, · · · , n, where Yi’s are data we can observe. And Xi’s, which are called the design points, are the locations we take observations.