Table 2. The similarities and differences between spatial autocorrelation and spatial cross-correlation.

Item	Spatial autocorrelation	Spatial cross-correlation
Correlation property	Intra-sample correlation	Inter-sample correlation
Correlation coefficient	I x = x T Wx, I y = y T Wy	R xy = x T Wy, R yx = y T Wx
ISWM	M (xx) = xx T W, M (yy) = yy T W	M (xy) = xy T W, M (yx) = yx T W
RSWM	M = nW = x T xW = y T yW	M = nW = x T xW = y T yW
Scatterplot	One plot	Two plots