I was playing around with ggplot2 using the following commands to fit a line to my data:
ggplot(data=datNorm, aes(x=Num, y=Val)) + geom_point() + stat_summary(fun.data = "mean_cl_boot", geom="errorbar", colour="red", width=0.8) + stat_sum_single(median) + stat_sum_single(mean, colour="blue") + geom_smooth(level = 0.95, aes(group=1), method="lm")
The red dots are median values, blue are the means and the vertical red lines show the error bars. As a final step, I used
geom_smooth to fit a line using linear smoothing so I used
method="lm". Along with the line, a dull shade was generated as well around the line. While I figured out how to remove it from the documentation, the option I used to turn it off is:
se: display confidence interval around smooth?
Can someone please tell me what I am supposed to understand from the shade around the line? Specifically, I am trying to understand how to interpret it. It must be some goodness-of-fit for the line perhaps but any extra information could be very useful to me. Any suggestions?