creating dummy variables

Hi,

Why do you write that dummy variables are not needed in R?. I would like you explain it.

As others have said --- do some self-study.  But a brief answer is that 
in any
"reasonable" modelling problem in which dummy variables might arise, R 
creates
the dummy variables that it uses automagically , behind the scenes, from 
the *factors*
whose levels correspond to the dummy variables.

Summary:  Learn about and understand *factors*; forget about dummy
variables.

     cheers,

         Rolf Turner