I received an answer that works but it feels hacky. I am wondering if the need to add a numeric version in the geom_hline data frame is a bug or intended behavior. Is there maybe a better approach I'm not seeing?
Tyler Rinker
PS I will post anything I learn back to the stackoverflow question.
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> To: ggp...@googlegroups.com
> From: fah...@faheem.info
> Subject: Re: geom_hline and facet grid with categorical yaxis
> Date: Wed, 15 May 2013 07:59:08 +0000
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