selection Although described as an objective method, there are many parameters which control the interpolated field. The choice of Δn, grid spacing Δx and as well influence the final result. Guidelines for the selection of these parameters have been suggested, however the final values used are free to be chosen within these guidelines. The data spacing used in the analysis, Δn may be chosen either by calculating the true experimental data inter-point spacing, or by the use of a complete spatial randomness assumption, depending upon the degree of clustering in the observed data. The smoothing parameter is constrained to be between 0.2 and 1.0. For reasons of interpolation integrity, Δx is argued to be constrained between 0.3 and 0.5. Notes Interpolation Spatial analysis