diff --git a/pyscript/rstat.py b/pyscript/rstat.py
index 187d942..09633bc 100644
--- a/pyscript/rstat.py
+++ b/pyscript/rstat.py
@@ -53,7 +53,7 @@ with_mode = RWrapper(rpy.with_mode)
 #as_py = RWrapper(rpy.as_py)
 
 
-def gdd(self, **kw):
+def gdd(**kw):
     r.library('GDD')
     filename = os.tempnam(None, 'rplot')
     robj = r.GDD(filename, type='jpg', **kw)