[R] Creating variables with different levels depending on conditions

[Miriam Gade]

Dear R-help-list, 

I started using R coming from the former use of SPSS, mainly writing my own
syntax. 
I do classical experimental cognitive psychology and am interested in the
cognitive control of task sequences (i.e. classification task). Especially I
am interested in the performance of the actual depending on the tasks
before. Thus, in SPSS I create variables like this one: 

Compute cond = 0. 
If (task_2=task) cond=1 else cond=2. 

task refers to the actual task and task_2 to the task performed 2 trials
before, cond=0 is used later to filter off the first two tasks in every
block. 

So far, I could create all variables I need in R like in SPSS. However, I
don't succeed creating a variable like "cond (=condition)" in R. I managed
to create a variable that is either true or false, but I would prefer a
categorical variable to get a table which I can use later for t-test and
anovas. I am bit puzzled that this simple syntax in SPSS has no equivalent
in R or am I just to blind to find it? All suggestions are cordially
welcome, miriam 



Dr. Miriam Gade
University of Zuerich
Institute of Psychology, General Psychology (Cognition)
Binzmuehlestr. 14, Box 22
CH-8050 Zuerich
Phone: +41 (0)44 6357-461