Estimating ozone risks using forest monitoring networks—results for science, policy, and society

Table 2 Description of explanatory variables (and their associated coefficients) included after stepwise selection involved in the reduced spatial model (in bold), built for each year within the study period

Year	Model	Intercept	X	Y	Elevation	T (°)	Spatial parameters
Year	Model	Intercept	X	Y	Elevation	T (°)	σ ²	φ	τ ²	AIC
2007	Total	2047.773	0.0000	−0.0004	0.0647	5.7128	4.5231	25,348.78	166.0890	191.5/−87.73
2007	Reduced	−35.0896			0.0509	4.2651	202.76	28,511.46	133.6205	191.7/−89.83
2008	Total	2330.699	−0.0002	−0.0004	0.0354	2.1798	1.27	2,088,596	117.6	175.9/−79.96
2008	Reduced	38.7184			0.0256	1.5598	613.4	44,516	72.31	177.7/−82.87
2009	Total	1891.927	0.0001	−0.0004	0.0781	8.1257	0.0000	0	106.1873	211.1/−97.54
2009	Reduced	−57.0797			0.0594	5.5266	319.1	20,712	38.81	211.7/−99.83
2010	Total	3976.102	0.0002	−0.0008	0.0594	5.0465	349.9	6297	11.56	236.2/−110.1
2010	Reduced	−58.0542			0.0617	5.6568	846.4	16,252	78.46	239.5/−113.7
2011	Total	3056.203	0.0000	−0.0006	0.0923	9.3345	0	0	294	237.6/−110.8
2011	Reduced	−191.771			0.1094	11.8085	724.3	15,542	70.95	236.9/−112.5

σ² the signal variance, φ range which indicates the distance at which the theoretical variogram reaches its maximum and represents the correlation function parameter, τ² nugget which represents the intercept of the variogram and determines the conditional or measurement error variance, AIC Akaike Information Criterion, used to estimate model fitting

ISSN: 1297-966X