The Moran's I statistic is a conventional measure of autocorrelation, similar in interpretation to the Pearson's Product Moment correlation statistic for independent samples in that both statistics range between -1.0 and 1.0 depending on the degree and direction of correlation:
Note that in this analysis all of the weights in the adjacency matrix (Sokal and Oden 1978) are set to 1, i.e. I is weighted by distance (h) between sample points rather than by simple adjacency. Calculating this statistic for a variety of lag distances produces an autocorrelogram such as that pictured below.
MoranI correlograms (both isotropic and anisotropic) appear in the Autocorrelation Window, on the MoranI tab. Pressing the Expand button on this tab brings up the Moran I window:
The Cloud/Scatter, right-click menu, and other commands work here as they do for the Variograms Window.