Unit 12 – Written Assignment 9: Logistic Regression


Load the data file unit 12_SPSSHW9_data_logistic reg.sav. A psychologist was interested in how accurately radiographers interpret ambiguous x‐ray images. He recruited a number of trainee radiographers, each of whom was shown an x‐ray and asked to determine whether or not it showed a fracture. The psychologist recorded the number of hours of training the radiographer had completed at the time of the study, whether the x‐ray showed a fracture or not, and whether the radiographer’s decision was correct.

  1. Identify the outcome and predictor variables. Indicate which of the predictor variables are categorical. (3 pts)
  2. Carry out the appropriate analysis to determine which of the predictor variables significantly predict the radiographer’s interpretation of the x‐ray. Include tables that show the model will predict the outcome. Also, include the beta, significance and Exp (B) as you discuss the results. (9 pts)
  3. Report the results of your analysis. Make sure and include the accuracy of the prediction of each variable. (7 pts)
  4. Extra credit: Conduct a discriminant analysis on the same data and interpret the findings. (10 points possible)
  5. Save and submit the SPSS syntax and output files used to complete items 1-3 (or 1-4 if attempting extra credit) above. The file names should begin with your first and last name followed by the homework number (e.g., John Doe HW10.sps; John Doe HW10.spv). (1 point)