polyexp_mul: Multivariate Polynomial Approximation

In estsyawo/RpacSPD: Spatial Panel Data models

Description

Take a k-order polynomial approximation of a multivariate φ(xi,xj) where both xi and xj are vectors of length l. This expansion involves l pairwise polynomial expansions using polyexp(). The expansion excludes terms that are solely in the first variable term because coefficients on them are not identified.

Usage

polyexp_mul(xi, xj, k)

Arguments

xi	vector of first variable terms
xj	vector of second variable terms
k	order of polynomial approximation

Value

vector of length l*k(k+1)/2

Examples

set.seed(2); xi=stats::runif(3); xj=stats::runif(3); polyexp_mul(xi,xj,2)

estsyawo/RpacSPD documentation built on Aug. 12, 2019, 5:22 a.m.