Fig. 5From: The effects of nutrients on stream invertebrates: a regional estimation by generalized propensity scoreThe causal effects of total nitrogen on invertebrates in different ecoregions of the Western United States. a Forested Mountains. b Great Plains. c North American Deserts. The black solid lines and black dashed lines are the mean estimations by generalized propensity score of the TN-IR dose-response function and the corresponding 95% confidence boundaries, respectively. The gray solid lines are the estimations by the general additive model in a and c and the estimations by simple linear regression in b. The gray dashed line in b is the estimation by multiple linear regressions and nearly overlaps the simple linear regression lineBack to article page