Table 1. Best-fit models of plant diversity.

	All sites	Urban	Desert
Model type	Spherical semivariogram	GLM	GLM
Data transformation	Log link	Log link	Square root
Spatial autocorrelation	Absent	Absent	Present
Predictor variables†	Land use	Family income (8.08)*	Elevation (7.59)***
	Urban (27.35)***	Median housing age (-6.65)*	Distance from urban center (-2.89)*
	Agriculture (10.21)*	Ever farmed (4.34)	Median housing age (2.50)
	Elevation (24.88)***
	Family income (12.72)**
	Ever farmed (6.04)

Significant variables are listed in order of importance as judged by the level of significance denoted by asterisks (***, P < 0.0001; **, P < 0.001; *, P < 0.01; no asterisk, P < 0.05). GLM, generalized linear modeling.

^†The appropriate test statistics are shown in parentheses, consisting of χ² values for all sites and urban models and a T value for the desert model.