spline.ensemble.RdEstimate model output based on univariate splines
spline.ensemble(gi.phii, median)matrix given as output from get.gi.phii
median value around which variance will be calculated
Accepts output from get.gi.phii (the matrix \(g(\phi_i)\)) and produces spline estimate of \(f(\phi)\) for use in estimating closure term associated with spline approximation