Recent content by raywood

  1. R

    Variable and Dataset Confusion

    I have imported an Excel spreadsheet into SAS as WORK.X1. I am trying these lines: proc freq data = x1 ; data x2 ; PhysicalAggression = (Aggress9 + Aggress10 + Aggress11 + Aggress12) /4 ; run; The log tells me that the Aggress variables are uninitialized. I guess this means that the...
  2. R

    Importing from Excel: SAS Newbie

    I have an Excel table. In SAS 9.2, I can use File > Import Data to bring that table into the SAS Explorer pane: contents of Work now includes that file. If I double-click on it, I get a VIEWTABLE pane showing the data. I am under the impression that it exists as a temporary file that I...
  3. R

    Bayes, and the Horse He Rode In On

    A professor presented this question: "If a cancer screen comes back positive in 68 of 75 cases of actual cancer and in 5 of 191 cases of no cancer, when the actual cancer rate in the total sample is 1/3, what is the probability of a false negative test result (patient has cancer but test comes...