R help - Aug 2010 - ROCR data input

Hi there,

I'm having some difficulty with the ROCR package. I've installed it
fine,
and the sample data works (ROCR.simple), however when I try to load my own
data it complains that there is an error in prediction as the number of
classes is not equal to 2. I read the data from a text file which contains
one column of probabilities and one column of binary 0 and 1. I then put it
into a data file called "prob", and try

 pred <- prediction("prob$probabilities", "prob$label")

which is when it comes up with an error. I think maybe I'm not importing it
properly?

probabilities
0.00000
0.00282
0.00001
0.04990
0.00009


label
0
0
0
1
0


Thanks for any assistance 
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Sorry, I'm new to R, and relatively new to statistics too so I'm still a
bit
unclear. The values in the post were only a sample of around 8400 rows. The
label has 1 or 0 (I thought this was the two classes needed). Each label row
has an equivalent probability. This is the data that I output from the
logistic regression analysis, but it is seemingly not the right format for
ROC curve analysis. There is a difference in how R displays the data, when I
type ROCR.simple it is in the format:

$predictions
  [1] 0.612547843 0.364270971 0.432136142.......
$labels
  [1] 1 1 0 0 0 1 1 1 1 0 1 0 1 0 0 0 1 1 1 0 0 0 0 ... etc.

whereas mine is in columns, e.g.

ID, labels, probs
8930     0 0.00070
8931     0 0.00036
8932     1 0.00000
8933     1 0.00002
8934     0 0.00001
etc.

That is why I think it is a format issue, but being new to R, I'm not sure
what I need to do to rectify it.
 I have attached the text file if this helps.

Thank you for your time,


http://r.789695.n4.nabble.com/file/n2328240/prob.txt prob.txt 
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