warning message from ezANOVA function in R

Question

I am new to R and I am trying to use ezANOVA to do a repeated measure factorial anova.

So I have a data frame named mus.df, which looks like the following (with more rows):

     sub path cond weight dir      mus
1   sub1 line   ff    0lb   l 0.537880
2   sub1 line   ff    0lb   m 0.508030

The dependent variable is "mus", and the independent variables are "cond", "weight" and "dir". "path" has the same value for a rows.

I called the ezANOVA function by

mus.ez=ezANOVA(data = mus.df,dv = mus,wid = sub,within = .(cond,weight,dir))

which seems to be working and gives me the result. However, I do receive a warning:

Warning message:
In `$.data.frame`(table2, GG) : Name partially matched in data frame

I am curious about what this warning message means. Did I do something wrong here?

Answer 1

are you using R Version 3.1. or higher?

Then I guess that you don't have to worry. As far as I know, this is just a change in the "partial matching" property in R. Partial matching means that R can call a variable in your dataframe, even if you do not spell out the whole variable name, but only parts of it. (e.g., in your case: >mus.df$co will lead to the output of the variable mus.df$cond)

As far as I know, R developers have made a change from Version 3.0.xx to 3.1.xx. Now, R will always give you a warning as soon as it encounters partial matching.

I suggest that this is also the problem in the ezANOVA()-function because it has, for instance, the variables "GG" and "p[GG]<.05"...The output of the function is nevertheless correct - as far as I can see.

But see also the following links for more details on this:

http://r.789695.n4.nabble.com/Deprecating-partial-matching-in-data-frame-td4661898.html

and

https://groups.google.com/forum/#!topic/ez4r/OWZ5SXo9ONI

I hope this helps!