"Effects" 

 I just happened across  this paper  on Steven Levitt's website entitled "What Does Performance in Graduate School Predict? Graduate Economics Education and Student Outcomes."  In addition to learning all kinds of fascinating things about the economics profession and professionalization process, I was struck by the non-causal use of the word "effect" when discussing the results of their statistical (er, econometric) models.   


  
I counted 8 uses in all, none of which were actually a believable effect of any kind.  To wit:  

 When admissions rank is excluded from the model, the math GRE has a statistically significant effect on micro, macro, and metrics grades, and the verbal GRE has a statistically significant effect on macro and metrics grades. (page 514, second column).   

 It's pretty hard for me to believe that GRE scores actually affect grades apart from their effect on grad school admissions (which affects a student's ability to get grades at all).  Clearly,  they  don't mean it causally, especially since they are dropping a post-treatment variable in and out of the model as they talk about it. 

 Ok, I get it that not everyone is as  apoplectic  concerned as I am about using the word "effect" to denote non-causal relationships.  I realize that the casual (non-causal) lingo of "effects" can just be short-hand among people who know better.  And sure, it's just kind of a fun paper.  But I would have expected this particular group of economists to have the catechisms of causal inference so well memorized that writing this kind of sentence would give them hives.