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help for rocss 
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ROC curve and other statistics for any classification method

        rocss dep_var prob_var [if exp] [in range] [, ncut(#)
                        savedata(filename) graph replace]

Description

   rocss calculates sensitivity, specificity, cumulative area under the ROC cur
> ve and percentage 
         of subjects correctly classified at user-specified probability cutoffs
> .

    dep_var is the binary outcome variable coded 0, 1.

    prob_var contains the estimated probabilities that dep_var==1.

    An example with four observations:

          id      dep_var    prob_var
           1         0          0.2
           2         1          0.8
           3         1          0.9
           4         0          0.3

Remarks

      Unlike lsens, rocss is not a post-estimation command and allows the user 
> to set arbitrary probability cutoffs.
      However, if used on predicted probabilities derived by logistic, logit or
>  probit, rocss 
      represents a flexible alternative to lsens.

Options

    ncut(#) specifies the number equally spaced probability intervals in the ra
> nge 0, 1. The number of corresponding 
            probability cutoffs will be (# + 1), at values 0, 1/#, 2/#, ..., 1.
>  
            The default is 10 equally spaced intervals.
    
    savedata(filename) specifies the name of a new dataset created to contain t
> he probability cutoffs 
            and corresponding sensitivity, specificity, cumulative area under t
> he ROC curve and the percentage of 
            subjects correctly classified. The dataset is saved in the current 
> directory.

    graph graphs sensitivity versus 1-specificity (help for lroc) calculated at
>  each probability cutoff.
    
    replace requests that if the dataset specified in savedata(filename) alread
> y exists, it should be overwritten.

Examples

    . webuse lbw, clear
    . logistic low age lwt smoke ptl ht ui
    . lstat
    . lroc, nograph
    . lstat, cutoff(0.30)
    . predict p

    . rocss low p  // compare the results
    . rocss low p, ncut(20) gr
    . rocss low p, saved(allsens)
    . rocss low p, ncut(80) gr saved(allsens) rep
 
Authors

    Nicola Orsini, Institute of Environmental Medicine, Karolinska
    Institutet, Stockholm, Sweden and Institute of Information Science and
    Technology, National Research Council of Italy, Pisa, Italy.

    Matteo Bottai, Arnold School of Public Health, University of South
    Carolina, Columbia, USA and Institute of Information Science and
    Technology, National Research Council of Italy, Pisa, Italy.

Support

        Nicola Orsini, http://nicolaorsini.altervista.org, Karolinska
            Institutet, Sweden
        nicola.orsini@imm.ki.se

Also see

          [R] logistic

On-line:  help for lroc, lstat, lsens, roc