How to update stat_smooth default row size in ggplot2?

Question

The new version of ggplot2 (2.0.0) changed the size of the stat line from 0.5 to 1. How can I change the default line size of stat_smooth to 0.5?

I knitted it

 update_stat_defaults("smooth", list(size = 0.5)) 

But that will not work.

Many thanks for your help.

Answer 1

As pointed out by rawr in the comments (and not marked as an answer within a month), the default line size of stat_smooth can be changed with:

update_geom_defaults("smooth", list(size = .5))

Other default sizes can be changed in the same way.