Last "+theme_bw()" to be deleted.
Try this:
ggplot(data1, aes(x=x1, y=y1))+
geom_point()+
geom_smooth(method="glm",
family="gaussian",aes(linetype="equation1"))+
geom_smooth(aes(x=x1, y=y1, linetype="equation2"),data=data2,
method="glm", family="gaussian")+
scale_linetype_manual(values =
c("solid","dashed"),name="Equations",
labels = c("Equation 1","Equation
2"),guide="legend")+
theme(plot.title = element_text(lineheight=.8, face="bold"),
legend.position="top")
--
GG
http://around-r.blogspot.it
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